And so we arrive at episode 13 of series 6. It's 5:02pm on 22 April 2011.
And the problem is that it's always 5:02pm on 22 April 2011 because time has gone "wrong". All of history is happening at once, so Winston Churchill is the head of the Roman Empire and Charles Dickens is being interviewed on Breakfast TV about his next Christmas Special.
It's all because River Song didn't shoot the doctor in Utah. Two versions of history have come into existence and it's all a mess.
The doctor describes to Churchill how he made preparations for his forthcoming death in Utah. He met the disembodied head of the blue-skinned guy from a previous episode who explained that The Silence want to prevent the Doctor asking the question that must not be answered. And the blue head guy actually knows what the question is...
The Doctor in the messed-up universe meets up with Amy who is now some sort of special agent. (She introduces herself as "Pond, Amy Pond".) She and her fellow agents all wear the eye patch thing. It turns out it's an eye drive (probably spelt "iDrive") that lets the wearer remember seeing The Silence when they are not around. She takes the Doctor to an Egyptian pyramid that has Area 52 painted on the side. There lots of The Silence are being help captive. Only they've been biding their time, waiting for the Doctor.
On top of the pyramid the Doctor and River get married, mainly so he can whisper his name in her ear, Except the Doctor lies and is not his name he is whispering, but rather "Teselecta", the name of the time-traveling humanoid space ship that has a miniature crew inside it from episode 8.
We discover that he asked the Teselecta to make itself look like him so it gets shot and the Doctor lives and all is right with the universe.
So having typed all the above I am struck by the fact that (a) it's not a stand alone episode and (b) it all sounds a little bit silly. In fact it's the second time that Steven Moffat has ended a season in a "not real" universe. While entertaining enough it does leave me with the somewhat dissatisfied feeling that the season adds up to less than the sum of its parts. I applaud the intent to do a complicated time travel story across two seasons but perhaps it would be better to stick to a more stand-alone season in 2012.
The glimpse of the Dalek in the trailer was slightly misleading, I'm sure intentionally. One Dalek briefly appeared at the start of the episode.
It's nice to see the Brigadier get a mention. The Doctor is told that he passed away at his nursing home.
Oh, I forgot, the question that must not be asked: