Peter Macintosh Firth (born 27 October 1953) is an English actor. He is best known for his role as Sir Harry Pearce in the BBC One show Spooks; he is the only actor to have appeared in every episode of the show's ten-series lifespan. He has given myriad additional television and film performances, most notably as Alan Strang in Equus (1977), earning a Golden Globe Award and an Academy Award nomination for the role.