I was very impressed when curator of maritime history Ian Murphy told me that he'd been filmed for Doctor Who. Unfortunately he wasn't part of tomorrow's big series finale so can't shed any light on what's in store there. Instead his expertise was required to help with a previous episode. He explained:
"I interviewed in Birmingham on the subject of 'maritime mysteries' for a short feature that will be used as a DVD extra for Doctor Who. It's for a re-release of an old John Pertwee episode from the 1970s, but I'm under orders not to reveal the episode title. The interview was based around disappearing ships and the DVD should appear sometime next year."