The Grand Moff told Radio Times:
We’re filming our first two-parter at the moment, which in fact are going to be episodes three and four of the new series, a brilliant script by Toby. Then there’s a couple more lined up from other writers, some new, some old, some middle-aged, frankly. It’s a little bit early to start teasing it but I’m a little bit excited. I think we’ve got some very, very good stuff going on.
What — were you expecting Moffat to name names?