Gein

Gein was a Brandragian whose organic craft (a Class lll Brandragian freighter) crashed into the North Sea before the Second World War. Gein disguised himself as human. Some time later, as a crew member of a naval submarine, he hijacked the boat to return to his craft. Unfortunately the ship had not completed its repairs. The arrival of the Eleventh Doctor, Amy Pond and Rory Williams in the TARDIS meant that Gein could return home by accepting a lift in the TARDIS. So that the craft wasn't discovered by the Nazis to change history, the Doctor changed the ship's biocomposition – making it an attractive, tasty and digestible food for sea life, which quickly ate it. It decomposed before it was discovered. (DWA: Sub-species)