Richard E Grant will appear in the 2012 Doctor Who Christmas special, the BBC has announced.
The actor, director and writer – best known for his lead role in 1987 British cult classic film Withnail & I – will appear alongside Tom Ward, aka Harry Cunningham in BBC1's Silent Witness.
"I played the Doctor in the digital animation Scream of the Shalka," said Grant, referring to the 2003 web serial made before the TV series reboot in 2005. "I'm honoured to be in the Christmas Special."
The festive episode - written by Steven Moffat and directed by Saul Metzstein - will mark the debut of Jenna-Louise Coleman as Matt Smith's new companion in the Tardis. Filming begins this week in Cardiff.