Thunderbirds Are Go



Thunderbirds Are Go is a 1966 British science-fiction adventure film based on Thunderbirds, a 1960s television series starring marionette puppets and featuring scale model effects in a filming process dubbed "Supermarionation". Written by Thunderbirds creators Gerry and Sylvia Anderson, directed by David Lane and produced by AP Films, Thunderbirds Are Go develops the franchise with a plot focusing on the futuristic spacecraft Zero-X and its manned mission to Mars. When Zero-X suffers a mechanical failure during re-entry, it is up to International Rescue, with the aid of the Thunderbird machines, to save the astronauts on board before the spacecraft is obliterated in a crash landing.

Filmed from March to June 1966 and premiering in December, Thunderbirds Are Go includes, in a first for an AP Films production, cameo appearances from puppets of real-life celebrities Cliff Richard and The Shadows, who also contributed to the musical score. It is also the first motion picture to have been filmed with an early form of video assist technology known as "Add-a-Vision", and incorporated landscape footage that was shot on location in Portugal. Special effects pieces, produced under the supervision of Derek Meddings and including rocket launch sequences, space shots and a miniature representation of the Martian surface, required six months to complete.

Despite positive initial reviews, which praised the film as a well-made cinematic transfer of the Thunderbirds television series, Thunderbirds Are Go soon proved to be a box office failure for the Andersons. The disappointment of this outcome was intensified by the knowledge that Series Two of Thunderbirds would be cut down to six episodes and that AP Films' upcoming television project would be a brand-new series, which would later be titled Captain Scarlet and the Mysterons and screened from 1967. To add to the lukewarm public response, negative critical reception of Thunderbirds Are Go has targeted, besides other aspects, the characterisation of the puppet cast, the running time dedicated to model and effects shots, and the fantasy dream sequence starring Cliff Richard and The Shadows, which has been described as a poor scriptwriting idea on the part of the Andersons.

Surprised by the underperformance of Thunderbirds Are Go, the United Artists distributors authorised the production of a sequel. However, Thunderbird 6 received a similarly unenthusiastic response on its release in 1968, and the Thunderbirds franchise was abandoned until the appearance of a reboot, starring live actors, in 2004. Meanwhile, the Zero-X astronauts were featured in their own strip in the Anderson-related TV Century 21 comic until 1969.

Plot
In 2065, the Zero-X spacecraft launches from Glenn Field as the first attempt at a manned mission to Mars. Unknown to Captain Paul Travers and his crew of two astronauts and two scientists, criminal mastermind the Hood has infiltrated the ship to photograph Zero-X ' s wing mechanism. When his foot becomes trapped in the hydraulics, the Hood causes a systems failure and Zero-X loses control. While the villain manages to extract his bloodied foot and parachute from the undercarriage, Travers and his crew eject in an escape pod and Zero-X crashes into the ocean before leaving Earth's atmosphere.

In 2067, at the conclusion of an investigation into the loss of Zero-X, the Inquiry Board of the Space Exploration Center reaches a verdict of sabotage. In the meantime, a second Mars mission has been planned. Days before the launch of the new Zero-X, International Rescue agrees to a request to organise security in view of the possibility of another sabotage threat. Jeff Tracy dispatches Scott to Glenn Field in Thunderbird 1, while Virgil in Thunderbird 2 and Alan in Thunderbird 3 are assigned to escort Zero-X as it leaves the atmosphere. Posing as a reporter at the pre-launch press conference, Lady Penelope ensures that Travers and the other four crewmembers are delivered St. Christopher brooches. Ostensibly for luck, these are in fact homing devices (a plot device previously used in the episode "The Duchess Assignment"). The next day, a search for Dr Grant's brooch checks negative. Scott unmasks the man waiting for lift-off on board Zero-X as the Hood in another of his disguises. The saboteur flees Glenn Field in a car, which Penelope and Parker pursue in FAB1. The Hood transfers to a speedboat, and then a helicopter piloted by an accomplice; Parker shoots the aircraft down with the Rolls-Royce's built-in machine gun and the Hood is seemingly killed. Meanwhile, the real Grant is returned to Zero-X and the spacecraft launches without further incident.

Mission accomplished, Penelope invites Scott and Virgil to join her at "The Swinging Star", a fashionable nightclub. Landing back on Tracy Island after escorting Zero-X, Alan feels unappreciated when Jeff insists that he remain on standby at base while his brothers spend the night partying. In bed, Alan experiences a surreal dream in which Parker "flies" him and Penelope in FAB1 to a version of The Swinging Star located in space. Present at the interstellar nightclub are Cliff Richard Jr and The Shadows, who perform a song titled "Shooting Star" and an instrumental, "Lady Penelope". The dream sequence ends abruptly when Alan plummets from The Swinging Star back to Earth and awakes to discover he has fallen out of bed.

After a six-week flight, the Zero-X Martian Exploration Vehicle lands on Mars on 22 July. While investigating the barren surface, the crew are puzzled to encounter strange rock formations arranged into coils. Space Captain Greg Martin blasts one of the structures with the MEV gun and Dr Pierce prepares to leave the vehicle to collect samples. However, the other formations stir into motion and reveal themselves to be one-eyed "Rock Snakes". Under attack from the extraterrestrials, which are able to shoot fireballs from their "mouths", the Zero-X explorers are forced to effect a premature departure from the Martian surface. Docking with the orbiting command module piloted by Space Navigator Brad Newman, the astronauts start the flight back to Earth.

As Zero-X re-enters Earth's atmosphere on 2 September, a lifting body launched to assist the controlled descent fails to interface, damaging the escape unit circuit (EUC). With Zero-X locked in descent and set to impact Craigsville, Florida, Jeff sends out Scott and Brains in Thunderbird 1 and Virgil, Alan and Gordon in Thunderbird 2. Winched into Zero-X ' s undercarriage, Alan must risk being trapped on board the spacecraft as Brains advises him on re-routing the damaged escape circuit. With Craigsville evacuated, Alan is left seconds to detach his cable. Travers and the others eject just in time, before Zero-X crashes spectacularly into Craigsville. Collected by Penelope and Parker in FAB1, Alan is driven to the real Swinging Star and Penelope, joined by the Tracy family, Brains and Tin-Tin, all disguised to conceal their identities, propose a toast to Alan as the "hero of the day".

Production
When shooting on Series One of Thunderbirds wrapped in late 1965, Gerry Anderson and his ITC financier, Lew Grade, agreed that a feature film adaptation, to be shot at the same time as the prospective Series Two, would be the next logical step in the expansion of the AP Films Thunderbirds franchise. With United Artists contracted to distribute the film and the Rank Organisation to exhibit, a budget of £250,000 was set  and Anderson and his wife, Sylvia, commenced work on the script at a Portuguese villa rented to them by Grade. The couple decided to base the plot on the American-Soviet "Space Race", in particular the 1960s contest to land astronauts on the Moon, but adapt this story for the futuristic Thunderbirds universe by changing the destination of the mission to Mars.

In the pre-production stages of their next puppet series, Captain Scarlet and the Mysterons, the Andersons would opt to script a second appearance of the Zero-X spacecraft to link the continuities of Thunderbirds and its sequel, which is supposed to be set in the same fictional universe. Captain Scarlet would also prove to be a progression from Thunderbirds Are Go in terms of its depiction of extraterrestrial life on Mars, although the Mysteron antagonists of this series would be more ambitious than the Rock Snakes of the film by actively seeking to attack Earth. The final rescue of the crippled Zero-X emulates that of the airliner Fireflash in the Thunderbirds episode "Operation Crash-Dive".

The role of director fell to David Lane, who had filled this position for several of the Series One episodes and also had editing and special effects experience at AP Films. Aged 24, with this appointment Lane became the youngest film director in Britain at the time. Frustrated with the creative limitations of puppets and concerned that the television series would not adapt well to a film, Alan Pattillo, the Andersons' initial choice, declined the role.

The insertion of Alan's dream sequence set at interstellar nightclub The Swinging Star was spearheaded by Sylvia, who expanded these scenes with a proposed musical interlude to be performed by puppet versions of Cliff Richard and The Shadows, Richard's backup band in the 1960s. Richard and Bruce Welch owned homes in Portugal near to the Andersons, and it was there that the two agreed to "appear" in the film as Supermarionation puppets. Also signed on to contribute to the film's score, Richard and the band recorded a song titled "Shooting Star", with Richard providing the vocals, and an instrumental piece, "Lady Penelope". Anderson concedes that the sequence does not progress the plot, stating in her autobiography that it was "sheer indulgence that would not have been possible on our television budget." Stephen La Rivière, documenting the making of Thunderbirds Are Go in his book Supermarionation: A History of the Future, considers the sequence the strangest ever created by AP Films.

Casting
The returning characters of the Tracy family, the other inhabitants of Tracy Island, Lady Penelope, Parker and the Hood are voiced, with one exception, by the Series One cast of Thunderbirds. Voice actors introduced in Thunderbirds Are Go are:


 * Jeremy Wilkin as Virgil Tracy. The only character whose voice actor was changed between Series One and Thunderbirds Are Go, since David Holliday had returned to the United States in the interim, the film and Series Two version of Virgil was voiced by Wilkin, an English-born Canadian actor who emigrated back to London in the 1960s.  Wilkin would maintain a professional relationship with the Andersons for seven years after the film, voicing the character of Captain Ochre in Captain Scarlet and the Mysterons, supporting roles in Joe 90 and also the character of The Bishop for The Secret Service, before minor appearances in two of the live-action Anderson productions of the 1970s, UFO and The Protectors.
 * Paul Maxwell as Zero-X Captain Paul Travers. Maxwell, a Canadian actor who often played American characters in 1960s British television, also provided voices for Thunderbirds Series Two and voiced the character of Captain Grey for several episodes of Captain Scarlet. His previous acting for the Andersons had come in 1963 with Fireball XL5, as the star character Colonel Steve Zodiac.
 * Alexander Davion as Space Captain Greg Martin. A French-born actor with experience on The Saint and Gideon's Way (in the role of Chief Inspector David Keen), Davion made one guest appearance on UFO in the 1970s.
 * Bob Monkhouse as Space Navigator Brad Newman. Monkhouse, an actor in such films as Carry On Sergeant (1958), would later host the British game show The Golden Shot between 1967 and 1972. He first approached Gerry Anderson for permission to film a comedy sketch based on Stingray,  but ended up agreeing to replace Alfred Marks, who had withdrawn from the film due to a fee dispute, as Newman.  Monkhouse recalled the conversation: "[Anderson] said, 'How much would you charge for the job?' I said, 'Gerry, I'd do it for nothing.' And that was the first time I ever heard the phrase, 'The price is right'." He affected an American accent for his parts in the film.
 * Neil McCallum as Dr Ray Pierce. With a role in the 1956 children's series Space School, after Thunderbirds Are Go Canadian actor McCallum made contributions to Captain Scarlet, UFO, The Protectors and (beyond the Anderson productions) Department S and Randall and Hopkirk (Deceased).
 * Charles Tingwell as Dr Tony Grant. Appearing in the medical drama Emergency – Ward 10 in the 1960s, Tingwell's work for the Andersons included Thunderbirds Series Two, Captain Scarlet (for which he was the voice of Dr Fawn) and one episode of UFO, after which he returned to his native Australia.
 * Cliff Richard as Cliff Richard Jr. Contracted in Portugal, where he owned a house "next-door-but-one" to Gerry and Sylvia Anderson, after negotiations with his agent, Peter Gormley, singer Richard says of his casting that he was "thrilled" to be part of the well-known and popular Thunderbirds franchise. Richard has fond memories of the making of his Supermarionation lookalike puppet: "It was quite a hoot ... I was never really sure if I looked like my puppet or it looked like me."
 * The Shadows (consisting of band members Brian Bennett, Hank Marvin, John Rostill and Bruce Welch) as Themselves, complementing Cliff Richard Jr in Alan Tracy's dream sequence set at The Swinging Star. Bennett remembers the puppet that was based on his likeness: "The first thing I did was to ask if I could keep him when filming was finished, but apparently he was to be turned into another character after the film had been finished."

Filming
Pre-production for Thunderbirds Are Go lasted three months, and a shooting schedule of sixteen weeks was allotted to coincide with the filming of episodes for Series Two. Principal photography commenced on 3 March 1966 and ended nearly four months later in late June. The AP Films staff were split into an "A" and a "B" Unit, "A" to concentrate on the film and "B" the television episodes. As a result of the division, henceforth the television shooting would be completed at the rate of one episode per month, whereas Series One had been filmed at a faster rate with the completion of two episodes in the same time.

While director of photography Paddy Seale and special effects supervisor Derek Meddings handled Thunderbirds Are Go, camera and effects roles for Series Two were delegated to their assistants, Julien Lugrin and Jimmy Elliott. Two unused buildings on the Slough Trading Estate were purchased to address the increased demands on the production team, combining with the pre-existing puppet workshop and art department and publicity centres to form an AP Films production base of five buildings. Converted by January 1966, one of these former factory units contained new puppet stages, while the other was dedicated to one large sound stage on which all model and effects work would be completed.

Cinematography
Thunderbirds Are Go was filmed in widescreen Techniscope, a subset of Technicolor, with an aspect ratio of 2.35:1. This represented a significant departure from the 4:3 picture used for the television episodes. The anamorphic lenses of Panavision, a popular system for Hollywood productions during the 1960s, proved to be unsuitable for special effects shots due to the depth of field of the cameras. Techniscope, on the other hand, could be used in conjunction with spherical lenses while attaining the "letterbox" image of mainstream films that were shot on 35 mm film. All AP Films productions had up to this point been filmed on Arriflex Cameras, but for the film these were replaced with the Mitchell brand.

Thunderbirds Are Go is also the first film to have been shot with the "Livingston Electronic Viewfinder Unit". Also known as "Add-a-Vision", this system consisted of a viewfinder, connected to video monitors, that was used to capture an image directly from the shooting camera. This enabled production personnel to inspect filmed footage on the set with a higher definition than had been possible with a more basic system used for AP Films television series. Add-a-Vision also benefited the puppeteers, who were stationed several metres above the set on gantries and had until this point not been permitted a useful view of the marionette movements below them. Based on German video assist devices, Add-A-Vision was developed by John Read, director of photography for Thunderbirds, in collaboration with Prowest Electronics, and also incorporated a form of playback function to aid staff while viewing rushes.

To enhance the illusion of the puppets, David Lane ensured that camera shots frequently omitted the tops of the heads and the visible control wires, and also incorporated low-angle shots for dramatic effect. Location shooting in Portugal was arranged for Lane, Derek Meddings and camera operator Alan Perry to film overhead landscape shots for the climax in which Alan rescues the Zero-X astronauts during re-entry. However, when the footage was deemed unsatisfactory, it was replaced with a painted backdrop made by associate producer Reg Hill.

Shots were also recorded for the end of Alan's dream, when the character tumbles from The Swinging Star back to Earth to discover that he has only fallen out of bed. To achieve this "spiralling shot", the team was carried by helicopter to an altitude of approximately 5,000 feet above an island off the coast of Portugal. The aircraft was then left to "autogyro" downwards as Perry recorded the view of the island looming up from below. Once again, however, the shot was declared inadequate and a model version was made at the AP Films Studios in Slough.

Puppets
Promising Television Mail that AP Films' latest venture would be "bigger and better than anything we have ever done before", Gerry Anderson realised that design defects would not be as quickly forgiven in a film adaptation as on the smaller screen. Puppets from the Thunderbirds television series were therefore expertly revamped, with new paint, wigs and costumes, while models and sets such as the Thunderbird machines were re-built from scratch with greater attention to detail. During production, the AP Films puppet wardrobe had a stock of over 700 costumes, with 150 extra costumes made mainly as spares in case of damage or loss.



Some of the main puppet cast to feature in the film, such as Scott Tracy, were re-made from the original marionettes, while previously unseen characters such as the Zero-X astronauts, Cliff Richard and the bandmembers of The Shadows were sculpted especially. Whereas guest star puppets for Series One had been recycled for each appearance and moulded in Plasticine, since this was the first occasion when puppets in an AP Films production were intended to represent real-life celebrities,  most of the supporting puppets were made from fibreglass to the same standards of workmanship as the main puppets.

From facial measurements and still photographs of the human templates, sculpting supervisor John Brown constructed Cliff Richard, while Brian Bennett was entrusted to Christine Glanville, Hank Marvin to Terry Curtis, John Rostill to Mary Turner and Bruce Welch to Tim Cooksey. Curtis went on to sculpt Zero-X crewmembers Captain Paul Travers and Co-Pilot Greg Martin, modelling the first on 1960s James Bond actor, Sean Connery and the latter partly on himself,  in addition to the Glenn Field Controller, Commander Casey.

The puppets of Thunderbirds Are Go are of identical proportions to the television puppets. However, while production of the film continued, AP Films developed a prototype with a latex mouth to result in more realistic movement of the lips and jaws. However, this animatronic technology proved to be insufficiently advanced and the idea was abandoned. For the later television series Captain Scarlet and the Mysterons, a brand-new puppet design of realistic anatomical proportions made its debut appearance when the solenoid of the lip-synch mechanism was relocated from the puppet head to the torso area.

Thunderbird 6, a sequel film shot simultaneously with Captain Scarlet, stars puppets intended to compromise between the first and second generations. Although the heads and hands remained large in relation to the torso and legs, the sculptors reduced the explicit caricature evident in the Thunderbirds television episodes and Thunderbirds Are Go to leave puppets sized in intermediate proportions.

Set design
The heads of the art department, Bob Bell and Keith Wilson, divided their efforts so that Bell contributed mostly to the film and Wilson to the Series Two episodes. Sets constructed by Bell especially for Thunderbirds Are Go included the Glenn Field Control Tower and Press Conference Room, the interiors of The Swinging Star, and re-designed versions of various locations on Tracy Island.

The appearance of the Space Exploration Center's Inquiry Room was influenced by Sylvia Anderson, who in her role as producer supervised design aspects and wanted the light-blue uniforms of the SEC officials to be vividly contrasted with a tangerine and black duotone backdrop. Director David Lane recalls that the Inquiry Room scene depicted a panel made up of 20 puppets, an achievement which would not have been possible in one of the Thunderbirds television episodes due to the smaller budget.

Of his approach to directing the film, Lane explains, "Thunderbirds Are Go was done like an episode but on a bigger scale. Whereas we would think that it might be nice to do a particular shot on the series but couldn't afford to, with Thunderbirds Are Go we just did it because we had the money." For the Swinging Star hall sequence, all the visual elements except Alan and Lady Penelope are displayed in black and white, with background characters appearing in the form of enlarged still photographs. On the surrealism of the Swinging Star scenes, aspects of which include pink space clouds made of dry ice and a giant guitar on which Cliff Richard and The Shadows perform part of "Shooting Star", Anderson explains that the production team "recreated a Busby Berkeley sequence", and that the appearance of puppet versions of real-life celebrities boosted the publicity value of the film.

Special effects


Derek Meddings and a team of 28 technicians completed the special effects shots for the film in six months. Their main assignments included the Zero-X launches, re-shot, widescreen launch sequences for the Thunderbird machines, the car chase between Lady Penelope and Parker in FAB1 and the Hood, scenes at The Swinging Star, the Mars shots involving the MEV and the mysterious Rock Snakes, and the ultimate destruction of Zero-X in the climax. Over 300 effects shot were completed with scale models. The team made use of the extra space afforded to them by the new special effects building to experiment with floor-level shots and other more creative camera angles.

The requirement to re-create the various Thunderbird machines was particularly problematic in the case of Thunderbird 2, as Meddings explains: "Unfortunately, its replacement was not only the wrong colour, it was a completely different shape. Although we had several more built in different scales, I never felt our model makers managed to re-capture the look of the original." Meddings was also responsible for the design of the Zero-X spacecraft, for the representation of which a fibreglass model, 7 ft (2.1 m) long, weighing 50 lb (23 kg)  and costing £2,500,   was built. The appearance of the Zero-X interior was based on then unfinished aircraft Concorde, a prototype of which was under construction at Filton Airfield in Bristol.

A long shot of a Zero-X lifting body falling through the atmosphere and exploding was the only special effects sequence filmed outside the building. Instead, it was mounted on a gantry at a nearby power station against a real sky backdrop and the team used Cordtex explosive strips, gunpowder, naphtha, magnesium and petroleum gel to create a "fireball" effect. Although it took months to construct, the studio's destruction of the Zero-X model was complete in two days. The effects shots for Thunderbirds Are Go later became so well known in the film industry that the work of Meddings and his team was consulted during pre-production on the 1986 James Cameron film, Aliens.

Editing


The film went through post-production in the autumn to be finished in time for a Christmas release. Len Walter, who had edited episodes for Series One, reprised his role for Thunderbirds Are Go. The workprint of the film ran more than 15 minutes over the maximum runtime permitted by United Artists, forcing Walter to cut several minor scenes that were not essential to the plot.

One set of deleted scenes charted the Space Exploration Center's attempts to enlist International Rescue to escort the second Zero-X. Meanwhile, the Hood telepathically contacts his half-brother Kyrano, coercing him to relay the Tracy family's actions. With the removal of the one scene in which he appears, Kyrano, another character voiced by David Graham, was completely cut from the film. A second deleted scene featured Lady Penelope and Parker en route to Glenn Field via New York, flying on board the aircraft Fireflash which made its first appearance in the pilot episode of Thunderbirds. Another deleted scene saw Jeff Tracy give a speech, broadcast worldwide over the Trans American TV Network.

No copies of the deleted scenes are known to survive. However, some still images remain. One photograph, in which Brains and Alan are seen standing behind a camera, is from the scene in which Jeff prepares for the broadcast of his speech, and appeared as the cover of issue 35 of FAB magazine. Another photograph, this one of the Hood in his temple with a film clapperboard in the foreground, has also survived. The only remaining film footage was edited into the 1968 Joe 90 episode "International Concerto", which includes a few seconds of video from the Trans American TV Network sequence.

Post-production
With Walter's editing complete, composer Barry Gray recorded the score in six sessions between 9 and 11 October at Anvil Studios near Denham in Buckinghamshire. To achieve proper symphonic sound, an orchestra of 70 musicians, aided by Gray's own electronic effects, was organised. The Band of the Royal Marines' rendition of the "Thunderbirds March" which accompanies the end credits of the film was recorded in one morning under the supervision of Gray and conductor Lieutenant Colonel Vivian Dunn at the Royal Marines School of Music in Deal, Kent. Three weeks were then allotted for visual wrap-up work, the insertion of the opening titles and minor animation, sound editing and dubbing. On its submission to the British Board of Film Classification in November, the film was awarded a U certificate.

An animated introduction to the film presents the main puppet cast, and is accompanied by the re-recorded version of the "Thunderbirds March". The end credits note the musical contributions of "Shooting Star" and "Lady Penelope" by Cliff Richard and The Shadows and the "Thunderbirds March" performed by the Band of the Royal Marines. Other credits are self-referential "acknowledgements" to individuals and companies who apparently assisted in the production of the film: these include the characters of Space Colonel Harris (the chairman of the Space Exploration Center committee) and Commander Casey, and the Century 21 "Space Location Unit". A humorous disclaimer then reads: "None of the characters appearing in this photoplay intentionally resemble any persons living or dead ... since they do not yet exist!"

Release
When filming for Thunderbirds Are Go concluded in June 1966, four episodes of Series Two had been completed on the monthly shooting schedule. Two additional episodes of Series Two, "Ricochet" and "Give or Take a Million", were filmed by "A" and "B" Units respectively. By December, Lew Grade had failed to sell the TV series to American broadcasters, recommending to Gerry Anderson that AP Films cancel production on Thunderbirds after the completion of six episodes for Series Two and start preparation for a new series, which would become Captain Scarlet and the Mysterons. For the development of this series, the staff of AP Films, on the advice of Merchandising Executive Keith Shackleton, agreed to change the name of the company to "Century 21 Productions", a name first carried by Thunderbirds Are Go to associate the film more closely with the related Anderson comic TV Century 21. Thunderbirds Are Go became the first Anderson project to be publicised, in full, as "A Gerry Anderson Century 21 Production".

Thunderbirds Are Go was screened for United Artists executives to a positive response before receiving its premiere at the London Pavilion in Piccadilly on 12 December 1966. Opening at a gala for the Barnardo's Charity, several crew and actors were in attendance, including Gerry and Sylvia Anderson, Grade, Cliff Richard and his sister Donella and The Shadows. The exterior of the Pavilion, adorned with neon and representations of the Thunderbird machines, led into the foyer in which puppets and models from the film had been put on display, with publicity posters promising audiences "The Most Advanced Spacecraft Ever Created"  and stipulating that "Adults Should Be Accompanied By Children". The Band of the Royal Marines provided a rendition of the "Thunderbirds March" both before and after the screening.

Reception
The release of Thunderbirds Are Go in December 1966 was one element of that year's "Thunderbirds Christmas" which witnessed a merchandising scramble to market tie-in media such as toys, games and novels. An initial review in Kine Weekly praised the film as a "colourful extension of Gerry Anderson's very popular television series", while the News of the World described it as "breath-taking entertainment". On 18 December, the Sunday Express published a similarly glowing review, in which the concept of the Zero-X mission to Mars was described as "awesome" and visuals commended: "Of course, the cast are all puppets, the sets, models, and the story unabashed nonsense. But it's great all the same. Your kids will take you, of course." In the Daily Mail, the transfer of the puppets from television to film was well received: "So who needs people? These handsome, stiff-necked, shiny-faced Thunderbirds puppets have broken spectacularly out of black-and-white TV and on to the cinema screen."

However, after the splendour of the premiere and the praise of some reviewers, when the Andersons departed on a tour of Britain to promote the film it was revealed that public interest was mediocre and box office revenue poor, as Gerry Anderson explains: "When we got off the plane at the first destination we were told that the film was in trouble. Cinemas were apparently half-full. When we got to the next big city we got more news that made us even more depressed – box office figures were inexplicably low wherever we went." Anderson proposes that the presence of Thunderbirds on television damaged the chances of its big-screen transfer, asserting, "The only thing we could think was that at that time the audience was not used to seeing a feature film version of a television show. So people would see Thunderbirds and think, 'We've seen it on television.'" Sylvia Anderson offers a similar explanation: "Although we still had our loyal television fans, they remained just that – firmly seated in front of their television screens and not in the cinema."

Supermarionation historian Stephen La Rivière suggests that the film also faced competition on its release in 1966 from other new family films such as Leslie H. Martinson's Batman and James Hill's Born Free. Reviews were, in general, turning less positive: although the Slough Observer described the film as "basically a Technicolor large-screen extension" of its television original, The Times was critical, asserting that the plotting and characterisation handed down from the television episodes were too thin to sustain a film and that the various air- and spacecraft launch sequences were intended less for visual appeal than padding to maintain feature length.

In his 1993 programme guide to the Anderson productions, John Peel comments that Thunderbirds Are Go is "well-made" and that it fulfils its promise to deliver visual spectacle, coming off as the more favourable of the two Thunderbirds films, although the plot is partly recycled from the television episodes, and the dream sequence is "painfully silly" and "embarrassingly awful". La Rivière agrees with Peel's view that the Thunderbird machines are underused, and that the extended model shots and infrequent appearances from the Tracy family may have been a disappointment to the intended audience of children.

Revisiting Thunderbirds Are Go from more recent perspectives has led to different interpretations: Jeff Stafford of Turner Classic Movies regards the film in its entirety as a "pop culture novelty as fascinating and endearing as a toy from one's childhood." He agrees, however, that the model sequences are protracted: "You'll feel yourself growing older as cranes and hydraulic lifts slowly – very slowly – prepare for a missile launch." Meanwhile, William Gallagher of BBC Online offers a positive review, asserting that Thunderbirds Are Go is "every bit as good" as the television series. However, he also suggests that its status as a film adaptation faithful to its original is an inherent weakness, and that Thunderbirds functions better as a television series, writing of the film's content: "Certainly there's no greater profundity or universal theme to the film, it is just an extended episode." Gallagher rates Thunderbirds Are Go three stars out of five, as does a review on the Film4 website.

Sequel
Despite the underperformance of Thunderbirds Are Go, Gerry Anderson received two awards for Thunderbirds in 1966, first with the presentation of a Silver Medal for Outstanding Artistic Achievement by the Royal Television Society, and then an appointment as an Honorary Fellow of the British Kinematograph, Sound and Television Society. Dismissing the box office failure of Thunderbirds Are Go as a one-off misfortune, United Artists advised Anderson to produce a second film, which would be titled Thunderbird 6. Anderson remembers the period of transition: "None of us ... could understand why the film hadn't succeeded, so it was decided we would make another one."

Budgeted at £300,000 – an increase of one fifth over Thunderbirds Are Go – in their approach to writing the sequel the Andersons decided to script a more light-hearted adventure to counter the seriousness of the original. However, Thunderbird 6 would also receive a less-than-enthusiastic public reception, spelling the end of Thunderbirds as a film and television franchise until the arrival of the live-action adaptation, Thunderbirds, almost four decades later in 2004.

Books and comics
Thunderbirds Are Go was novelised by writer Angus P. Allan and published by Armada Books in 1966. The events of the film from the perspective of the Zero-X mission were also adapted for a four-part "photographic picturisation" in the comic TV Century 21 (launched in 1965 and renamed TV21 in 1968). After this re-telling of the events of Thunderbirds Are Go, comic strips published until 1969 charted the continuing adventures of the astronauts, led as ever by Captain Paul Travers, in missions to the other planets in the Solar System, and then beyond, on board the "Mark III" model of Zero-X.

The connection between Thunderbirds and its successor series, Captain Scarlet and the Mysterons, also featured prominently in issues published between June and September 1967, leading up to the television debut of Captain Scarlet. In these issues, Captain Black of the Spectrum Organisation commands another Mars mission in Zero-X and (as depicted in the pilot of Captain Scarlet) falls under the manipulation of another native extraterrestrial race besides the Rock Snakes, "The Mysterons". The involvement of Zero-X reaches a climax when the spacecraft, occupied by the possessed Black, lands back at Glenn Field and the Mysteron agent escapes capture by the authorities.

Home video
A re-recorded version of Barry Gray's score received vinyl releases from United Artists in 1967 and Silva Screen Records in 1987. The collection was later converted for CD in 1990 and re-released by EMI in 1992. Also comprising four tracks of incidental music from the Thunderbirds television episodes, the 1992 release consists of items titled "Alan's Dream", "Martian Mystery", "Astronauts in Trouble" and "Swinging Star" (composed by Gray), "Shooting Star" (performed by Cliff Richard and The Shadows) and "Lady Penelope" (performed by The Shadows), and two versions of both the "Thunderbirds Theme" and "Zero-X Theme" (as composed by Gray or performed by The Shadows). The original recordings of the film soundtrack of Thunderbirds are Go and Thunderbird 6 were released by La-La Land Records on a limited edition CD in 2014.

In Regions 2 and 4, Thunderbirds Are Go was first released on DVD by MGM in 2001, with special features including an audio commentary with director David Lane and producer Sylvia Anderson,  the theatrical trailer,  stills  and production galleries. A 2004 "International Rescue Edition", including Region 1 and marketed both separately and as part of a box set with the sequel film, Thunderbird 6, boasts remixed Dolby Digital 5.1 surround sound  and expands on the original extra material with three documentaries detailing the production of the film. A limited edition high definition Blu-ray Disc release of Thunderbirds are Go and Thunderbird 6 was released on 13 May 2014.