Regular Cast

Matt Smith (The Doctor), Karen Gillan (Amy), Arthur Darvill (Rory)

Guest Cast

River Song (Alex Kingston), Madame Kovarian (Frances Barber), Dorium Maldovar (Simon Fisher-Becker), Winston Churchill (Ian McNeice), Dr Malokeh (Richard Hope), The Silent (Marnix Van Den Broeke), Charles Dickens (Simon Callow), Woman on television (Sian Williams), Himself (Bill Turnbull), Herself (Meredith Vieira), Gideon Vandaleur (Niall Greig Fulton), Barman (Sean Buckley), Gantok (Mark Gatiss), Dr Kent (Emma Campbell-Jones), Nurse (Katharine Burford), Carter (Richard Dillane).

1. This is the first and only episode of Doctor Who to air on the same night as an episode of fellow BBC Saturday night drama Merlin. The first episode of Merlin Series 4,
2. The Darkest Hour, was broadcast right after The Wedding of River Song.
   Meredith Vieira, co-host of the American morning news/chat programme Today, filmed her cameo during a visit to the Upper Boat Studios as part of a profile of
3. Doctor Who produced for Today. The profile aired on 9 May 2011, contained several minor spoilers for this episode. It revealed the cameo appearance by Richard Hope as Malohkeh and the return of Ian McNeice as Winston Churchill. Appearances by several Cybermen served as a "false flag" spoiler suggesting they might also appear in the episode. They did not.
4. This is the first series finale of the revived series not to be a multi-part episode. In fact, it is the first series finale ever to only be one episode, though it can be seen to be completing the multi-part story started in The Impossible Astronaut. It was also the first-series finale of the revival series not to feature a "classic series" adversary as the main antagonist, even thought it featured a cameo of a Dalek.
5. In The Impossible Astronaut the versions of the Doctor give their ages as 909 and 1103. The Doctor has apparently lived for almost two hundred years between these two episodes. Writer Gareth Roberts indicated in an interview that this is indeed two hundred years after The God Complex for the Doctor and he spent these years "waving" at Amy and Rory through history books.
6. The hat shot off the Doctor's head by River in The Impossible Astronaut was a copy made by the Teselecta.
7. This was the last episode to be covered by Doctor Who Confidential due to that series' cancellation. Starting with The Doctor, the Widow and the Wardrobe, the official Doctor Who website would feature short making-of videos after each episode's transmission.
8. A message that "Doctor Who Will Return" appears at the end of the episode.