Now this was different. The fun starts when the Doctor and Donna arrive at an English country house in 1926, just in time to crash a party. While they were arriving and Donna was changing into something more suitable, Professor Peach was lying dead in the library after finding the answer to a question that had been bothering him and having an encounter with a bit of lead pipe and what seemed to be a rather large wasp.
Once Lady Edison is assured that the Doctor isn’t the Unicorn (a jewel thief, not a pointy horse), the usual introductions are performed, including the guest of honour introducing herself to Donna:
Guest: Agatha Christie
Donna: What about her?
Yes, it’s the actual Agatha Christie, and it’s the day before her mysterious disappearance. And then the fun really starts. And the fun takes the form of a moderately traditional country house murder mystery, complete with swirly flashback effects and a rising body count. Of course, this being Doctor Who, it also involves a shape-changing Vespiform, or bloody enormous wasp as most people would call it, that’s not at all friendly, and may be one of the guests.
And as it’s a murder mystery, I won’t give away the whole plot, or to many details. So I’ll just touch on some highlights. It seems everyone in the house has a secret of some kind, whether it’s not being who they say they are, having done something many years earlier that wasn’t quite appropriate, being a little bit more friendly with a footman than would be considered appropriate, or indeed being an alien wasp thingy.
The Doctor teams up with Agatha Christie to do some proper investigation, Donna finds a good use for a magnifying glass, we learn that the Doctor knows how to get over a little bit of cyanide poisoning, and we do get to find out why Agatha disappeared only to turn up in a Harrogate Hotel.
All in all, a nicely silly episode with a lot of laughs, and a moderately low body count. No world-shattering threats, no vast evil conspiracies, just a nice run-around with fun dialogue and a nicely created wasp.
Note: There is no Doctor Who episode next Saturday, as some bizarre ritual known as the Eurovision Song Contest is on. So in two weeks, we get the beginning of Steven Moffat’s story involving something very nasty in a library.
 Professor Plum couldn’t make it, apparently.