The opening stories of Season 6 of Doctor Who are all stand-alone adventures without much of a direct link from one story to the next. The Dalek adventure of "Asylum of the Daleks" jumps into the prehistoric space of "Dinosaurs on a Spaceship" and on again to the cowboy romp "A Town Called Mercy" because they represent little trips made by Amy and Rory with the Doctor, who takes them back home again afterwards, rather than one long rolling adventure of three travelers.

"Dinosaurs on a Spaceship" is where we first meet Rory's dad Brian, played by Mark Williams, and he'll later come to represent the life at home that Amy and Rory wish to return to, to recharge from their adventures.

Here are a few things to keep an eye out for, the next time you watch:

(The episode is available on iTunes and Amazon.)

Steven Moffat offered Chris Chibnall the chance to write another Silurian-based adventure (after "The Hungry Earth" / "Cold Blood") in 2011, having come up with the title "Dinosaurs on a Spaceship" as a riff on the self-explanatory title to the movie Snakes on a Plane.

The Doctor jokingly claims that he is a Sagittarius, "probably." Although clearly a joke, it's worth noting that November 23, the date of the first broadcast of Doctor Who and the unnofficial birthday of the Doctor, would make him a Sagittarius, if that actually was his real birthday.

Chris wanted the Doctor to arrive with a "gang" made of famous historical figures, which is why he dragoons Nefertiti (whose final days are lost to history) into coming with him. But his original idea was that the other person would be Charles "Buffalo" Jones, the frontiersman who helped prevent the extinction of the American bison in the late 1800s. However, Steven Moffat already knew the next trip for the Doctor would be to the Wild West, in "A Town Called Mercy" and asked for a change to avoid cowboy overlap. Chris invented John Riddell, basing him on Allan Quatermain, from H. Rider Haggard's 1885 novel King Solomon's Mines).

As the Doctor realizes the TARDIS has picked up Brian, Rory's dad, the Doctor rounds on Rory, saying "I'm not a taxi service, you know." This echoes similar moments in the past, specifically when the Fifth Doctor refuses to take Adric back to E-Space in "Earthshock" ("There isn't a taxi service goes back and forth!" and when the Doctor chides River Song for making him pick her up in "The Time of Angels" ("I'm nobody's taxi service"):

https://www.youtube.com/watch?v=gUw8fE6S1eU

Brian Williams refers to the Doctor sarcastically as "Arthur C. Clarke", the British science fiction writer and creator of Clarkes Law—"Any sufficiently advanced form of technology is indistinguishable from magic." This has been referenced and paraphrased in both new and classic Doctor Who. The Captain used the the phrase "indistinguishable from magic" in the Fourth Doctor story "The Pirate Planet," the Seventh Doctor quoted it to his companion Ace in "Battlefield," before stating that "the reverse is true," and describing a parallel universe of magic and technology. And in "The Girl Who Died," just before trying to win over a Viking village, the Twelfth Doctor said this of his yo-yo: "To the primitive mind, advanced technology can seem like magic."

The face of Sunetra Sarker, who plays Indira, the person with their finger on the button of the Earth missiles, will have been a familiar face to British viewers, as she's a stalwart of the BBC hospital drama Casualty, in which she plays Dr. Zoe Hanna:

https://www.youtube.com/watch?v=s9pURyNuONY

This episode contains two British comedy double actsWhen dispelling the doomy predictions of Nefertiti and Riddell, Amy exclaims, "alright, lighten up, Chuckle Brothers!", which is a reference to Barry and Paul Chuckle of the British children's TV show Chucklevision, who specialize in comedy slapstick in the vein of Laurel and Hardy, with their genial prattling and catchphrase "to me, to you". They also had a stab at making a hit single with the rapper Tinchy Stryder:

https://www.youtube.com/watch?v=EBtd3H3Qdi8

And the voices of the two robots are provided by David Mitchell and Robert Webb, stars of great British TV comedies Peepshow, Back and their own sketch show That Mitchell and Webb Look, which contains this exceptional skit about German soldiers:

https://www.youtube.com/watch?v=hn1VxaMEjRU

The costumes for the robots came from Millennium FX, regular suppliers of Doctor Who costumes, who had made them for a CBBC game show called Mission: 2110, in which they were called Roboidz. For Doctor Who use, the costumes were deliberately scuffed up and repainted:

https://www.youtube.com/watch?v=n0Ua7p-8UrI

Speaking of the robots, when they're switched off, they sing the old British music hall song "Daisy Bell", as a nod to the computer HAL doing likewise in Stanley Kubrick's 2001: A Space Odyssey (written, incidentally, by Kubrick and Arthur C. Clarke). In the movie, that song was intended to suggest a regression in computer sentience back to the IBM 704, the first computer to be programmed to sing using speech synthesis, in 1961.

https://www.youtube.com/watch?v=41U78QP8nBk

But "Daisy Bell" also featured in the Fourth Doctor adventure "The Talons of Weng-Chiang", as the Doctor and Leela visited a music hall in 1889. The curious thing about that is that the song wasn't actually composed by Harry Dacre until 1892.

Now go back and read the entire 10 Things You May Not Know About Doctor Who archive.