David Bradley
David Bradley (born in Yorkshire, England) provided the voice of the Shansheeth in The Sarah Jane Adventures story Death of the Doctor. He later appeared in Doctor Who as Solomon in Series 7's Dinosaurs on a Spaceship and also played the First Doctor in Series 10s The Doctor Falls.
Bradley made his third DWU-related appearance in 2013, when he played William Hartnell — the man who portrayed the First Doctor — in the docu-drama, An Adventure in Space and Time. He would later go on to portray the First Doctor directly in a surprise appearance in The Doctor Falls.
Outside of the Doctor Who franchise Bradley is known for, among other things, Broadchurch, written by Chris Chibnall, and playing Argus Filch in the Harry Potter movies and Walder Frey in the HBO series Game of Thrones.