David Troughton
From Tardis Wiki, the free Doctor Who reference
The son of Patrick Troughton, the actor who played the Second Doctor, David Troughton is also an actor, and has appeared in several Doctor Who serials. His major role was in the Third Doctor story "The Curse of Peladon," in which he played King Peladon; he also appeared in "The War Games" as Private Moor and "The Enemy of the World" as a guard. He will appear in the new series and play a character called Prfesor Hobbs in the episode Midnight.
Beyond Doctor Who, Troughton is also a member of the Royal Shakespeare Company and a renowned classical actor.