Robert Powell is an English actor who is known for the title roles in Mahler and Jesus of Nazareth, and for his portrayal of secret agent Ri…Robert Powell is an English actor who is known for the title roles in Mahler and Jesus of Nazareth, and for his portrayal of secret agent Richard Hannay in The Thirty Nine Steps and its subsequent spinoff television series. Other major screen roles have included Tobias"Toby" Wren in the BBC science-fiction programme Doomwatch, David Briggs in the sitcom The Detectives alongside Jasper Carrott, and Mark Williams in the medical drama Holby City.