In 2367, Earth's security forces are on high alert as an unidentified spaceship hurtles towards the planet. The Doctor assembles a team to investigate, including the legendary Queen Nefertiti, a big game hunter named Riddell, Amy, Rory... and, inadvertently, Rory's father Brian. Materialising aboard the mystery ship, they're surprised to find it populated by dinosaurs. It turns out to be a Silurian ark, launched from Earth millions of years ago and now hijacked by a vicious criminal named Solomon. With time running out before the vessel is annihilated, the Doctor may be forced to extreme measures to save both the dinosaurs and his friends.

The starting point for Dinosaurs On A Spaceship was its title. At a meeting on July 8th, 2011, Doctor Who executive producer Steven Moffat suggested it to writer Chris Chibnall, who had last contributed Season Thirty-One's The Hungry Earth / Cold Blood. It was inspired by the shamelessly direct moniker of the 2006 movie thriller Snakes On A Plane starring Samuel L Jackson, which had previously prompted Season Thirty-One's The Vampires Of Venice. The scenario was also motivated by the stated desire of effects house The Mill to create computer-animated dinosaurs for Doctor Who. Beyond the basic premise, Moffat also proposed that Chibnall should incorporate two impressive robot costumes which had originally been designed by Millennium FX for the previous year's CBBC game show Mission: 2110. Millennium's Neill Gorton felt that the “Roboidz” had been underutilised on Mission: 2110, and could easily be retooled for use on Doctor Who.

Another important facet of Dinosaurs On A Spaceship would be its place in the character arc of the Doctor's friends, Amy and Rory. Whereas most previous companions had been essentially unchanging throughout their time on Doctor Who, Moffat intended Amy and Rory to evolve through three distinct stages. In Season Thirty-One, Amy was the primary companion who only occasionally travelled with Rory -- an arrangement which echoed that of Rose Tyler and Mickey Smith during Seasons Twenty-Seven and Twenty-Eight. During Season Thirty-Two, Amy and Rory became the first married companions to journey in the TARDIS and, furthermore, conceived a child who would grow up to become their sometimes-ally River Song.

Steven Moffat wanted to explore what happened to the Doctor's companions after their travels in the TARDIS had finished

For Season Thirty-Three, Moffat wanted to explore what happened to the Doctor's companions after their travels in the TARDIS had finished. To this end, Amy and Rory had ostensibly returned home at the conclusion of the previous year's The God Complex. Moffat rejected the notion that the Doctor would never pay his former companions a visit, deeming it inconsistent with his character. As such, the first part of Season Thirty-Three would chronicle the times that the Doctor, Amy and Rory were reunited. Initially four episodes long and later extended to five, the arc would culminate in the characters' final departure from Doctor Who. It would also signal the start of a protracted break in transmission: only the 2012 Christmas special would air before the season resumed in the spring of 2013. This was a plan developed by Moffat in discussion with Karen Gillan and Arthur Darvill, who had approached him in 2011 to indicate their desire to wind down their tenures on the show.

Chibnall submitted an outline for Dinosaurs On A Spaceship on October 10th. For the villain, Solomon, he thought in terms of a futuristic Somali pirate, of the type that had been terrorising ships in and around the Gulf of Aden since 2005. Meanwhile, Chibnall had obtained Moffat's blessing to introduce Brian Williams, father to Rory. The writer knew that his episode would be one of the last to feature the character, and so he wanted to explore the Williams family while he had the chance.

In addition to Amy, Rory and Brian, Chibnall was keen to depict the Doctor adventuring with a “gang”. Its other two members were originally both real historical figures, but only the Egyptian Queen Nefertiti would be included in the final narrative. Reigning in the mid-fourteenth century BC alongside her husband, the Pharoah Akhenaten, Nefertiti was traditionally depicted as a woman of great personal strength. Her involvement was also appealing because she -- debatably -- disappeared from the historical record, with no clear evidence of the manner of her death. Consequently, Chibnall felt that Nefertiti could have plausibly gone off travelling with the Doctor, ending her days elsewhere in space and time.

The other person Chibnall wanted to incorporate was frontiersman Charles “Buffalo” Jones (1844-1919), who helped save the American bison from extinction. However, Moffat was concerned that this character was too similar to the cowboys of A Town Called Mercy, the story which would follow Dinosaurs On A Spaceship in the season schedule. As such, Chibnall instead devised the fictional big game hunter John Riddell; he was inspired by characters like Allan Quatermain, the hero of H Rider Haggard's 1885 adventure novel King Solomon's Mines. Chibnall's intention was that Riddell had once saved the life of the Doctor, who was now giving him one last thrilling experience -- because Riddell was fated to die the day after he was collected from the African plains. This backstory was eventually lost in editing.

Originally, Nefertiti knocked the Doctor out and gave her own life to destroy Solomon's ship

The major change that affected Dinosaurs On A Spaceship during the drafting stage involved its climax. Originally, Nefertiti knocked the Doctor out and gave her own life to destroy Solomon's ship. When this denouement was felt to be too similar to other self-sacrificial moments in the final cycle of Amy/Rory episodes, Moffat instead suggested that the Doctor and Nefertiti could be saved by having the TARDIS materialise around them as the missiles struck Solomon's pod. Subsequently, however, Moffat decided that this approach lacked drama. He also wanted to explore what happened to the Doctor when he travelled without regular companions, and so the Time Lord would now abandon Solomon to his death.

Dinosaurs On A Spaceship would be the second episode of Season Thirty-Three. Although the realisation of the title creatures would be partly accomplished through practical means, a substantial amount of computer animation would also be required. To give The Mill sufficient time to complete the episode's effects work, it was decided that Chibnall's script would form part of the year's first production block. Made alongside A Town Called Mercy, it would be directed by Saul Metzstein, who had previously been approached to work on Season Thirty-Two. The demands of the dinosaur animation also meant that any other complex sequences had to be curtailed. As a result, Chibnall had to drop a scene in which a pair of ankylosaurs inadvertently launched the TARDIS out of an airlock and into space.

A key casting decision for Dinosaurs On A Spaceship was the role of Brian Williams. Drawing upon suggestions made by Darvill, the part went to Mark Williams. His numerous credits included the sketch comedy The Fast Show and the first season of Red Dwarf, plus movies like Shakespeare In Love, Stardust and the last seven Harry Potter movies, in which he played Arthur Weasley. He had also appeared in The Eternal Summer, a Fifth Doctor audio play released by Big Finish Productions in 2009. Meanwhile, Bleytal would be portrayed by Richard Hope, as suggested by Chibnall's script. This would be his third appearance as a Silurian, after previously playing Dr Malohkeh in The Hungry Earth / Cold Blood and the Season Thirty-Two finale, The Wedding Of River Song. Having already named Silurians after Doctor Who writer Malcolm Hulke and script editor Terrance Dicks, Chibnall devised Bleytal as a reference to Barry Letts, the producer of Doctor Who when the Silurians were first introduced.

The engine room sequences were shot on Southerndown Beach, although recording was curtailed by a rainstorm

Recording for Dinosaurs On A Spaceship began on February 17th, 2012, when Bleytal's message was taped at Doctor Who's regular studio facilities in Upper Boat. More than four months had elapsed since work concluded on the 2011 Christmas special, The Doctor, The Widow And The Wardrobe, while nine and a half months separated the end of principal photography on Season Thirty-Two and its start for Season Thirty-Three. After the weekend, filming on February 20th began at a residence on Church Road in Penarth, which posed as Amy and Rory's house -- the third dwelling to serve this purpose in the preceding eleven months. Cast and crew then adjourned to Upper Boat for the material in the cave, plus the effects shot of Brian looking down on the Earth. Studio production continued on the 21st, when Metzstein focussed on scenes in and around Solomon's pod. On February 22nd, the engine room sequences were shot on Southerndown Beach, at Southerndown in Ogmore Vale, although the day's activities were curtailed by a rainstorm.

The rest of Dinosaurs On A Spaceship was made at Upper Boat, starting with scenes in the Bio-Lab on February 23rd. On the 24th, cast and crew moved to the massive spaceship corridor, which eclipsed the Underhenge from Season Thirty-One's The Pandorica Opens / The Big Bang as the largest set ever constructed for Doctor Who. Recording there continued through to March 1st, with the exception of a day off on Sunday the 26th. A key feature of this work was the presence of Tricey the triceratops, which was partly realised as an animatronic prop boasting a head designed by Gary Pollard. An alumnus of the Jim Henson Workshop, Pollard hewed to modern theories about triceratops physiology, although some license was taken to enlarge the eyes in order to make Tricey more endearing. Meanwhile, part of March 1st was also spent recording material outside Solomon's pod, as well as various inserts. The 2nd then saw filming move to the set for the control deck.

Following the weekend, more material in Solomon's pod was taped on March 5th, after which Metzstein turned his attention to A Town Called Mercy. Recording for Dinosaurs On A Spaceship resumed on March 19th, when the 1902 sequences were completed alongside the remaining footage aboard and around the pod. The last day of work on the episode was March 23rd, which was devoted to the scene in Ancient Egypt, those at the Indian Space Agency monitoring headquarters, and further pick-up shots.

With Doctor Who only returning for a handful of weeks in the autumn of 2012, Moffat wanted every episode to feel indispensable. Eager to paint the five adventures as being like miniature blockbuster movies, he acted on a suggestion made by his fellow executive producer, Caroline Skinner, to distinguish each one with a specially-designed variant of the Doctor Who logo. As such, Dinosaurs On A Spaceship gained a version with a scaly, reptilian texture. When the episode aired on September 8th, Doctor Who moved to 7.35pm, fifteen minutes later than the previous week's season premiere.

• Doctor Who Magazine Special Edition #33, Spring 2013, “Dinosaurs On A Spaceship” by Andrew Pixley, Panini UK Ltd.
• Doctor Who: The Complete History #71, 2015, “Story 227: Dinosaurs On A Spaceship”, edited by John Ainsworth, Hachette Partworks Ltd.