It's being written by Steven Moffat, it'll have Matt Smith and Jenna-Louise Coleman in it, and now we know one more thing about the Christmas special; it's being directed by Jamie Payne. So far he's only directed one Doctor Who story - "Hide" - but he has experience working on several of the usual suspects: Ashes to Ashes, Survivors, Primeval, that sort of thing. His official website is here, and the Independent ran a short article about his experiences directing Paul McGann.

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