Matthew Bannister on

Dick Gregory, the African American comedian and civil rights activist who was also a dietician to stars like John Lennon and Mohammed Ali.

Jeannie Rousseau who spied on the Nazis' secret weapons programme.

Wayne Lotter, the South African elephant conservationist who has been shot dead in Tanzania.

Sean O'Callaghan, the leading IRA member who turned informer. He helped to stop a bomb attack which would have killed the Prince and Princess of Wales.

And the jazz guitarist John Abercrombie.