Ooops. From Bleeding Cool:
Found in the back of a cab in Cardiff. Image posted to Facebook with the line “found Dr Who script in the back of a taxi. Cheeky spoilers anyone?” before being posted to Reddit.
The finder did try to get in touch with the BBC and the production team to return the script without joy, though after the Reddit posting, things took a natural turn and arrangements were made.
We can of course note that Jenna-Louise Coleman‘s character is called Clara, Being Human‘s Jason Watkins is in this episode, and so is Warwick Davies, playing “Porridge”.
More tidbits at Bleeding Cool. Nothing spoilerish.
ETA: It has been pointed out to me that it was probably not Gaiman himself who left his script (as was suggested by the original title of this post), but one of the cast members. Sorry, Neil…
(If you stumble across a cool Doctor Who thing, feel free to email me with a link.)