Marcus Mortimer Director Warren Clarke George Cragge Actor Stephen Fry Radio 2 Controller Actor Richard Griffiths Geoffrey Crichton, Potter Actor Rik Mayall Dominic De'Ath Actor Richard Wilson Lord Tone Actor John Bird Radio 4 Controller Actor Alun Armstrong DCI Frank Jefferson Actor Siobhan Redmond Ms Sin Actor John Sessions Hercules Fortescue Actor Rachel Fielding Laetitia Tone Actor Paul Ansdell Home News Organiser Actor Robert Austin Jeremy Inchcape Actor Keith Barron Jim Wilkes Actor Andrew Burt Chief Commissioner Actor Victoria Carling DS Marten Actor Colum Convey Agent Actor Kevin Eldon Video shop assistant Actor Rebecca Front Beth Parsons Actor Mark Gatiss Junior Detective Actor Simon Godley Henry Potts Actor Colin Guthrie Second Studio Manager Actor Ian Harker First Studio Manager Actor Anne Harries Madame Speaker Actor Peter Hobday World at One Presenter Actor Melanie Hudson "Oh Jesus" P.A. Actor Lee Ingleby Paul, Reform Party Worker Actor Arthur Kelly Home Secretary Actor James McCarthy Bamber Simpson Actor Geoffrey McGivern Clarence Twist Actor Alistair McGowan Murderer's Voice Actor Sarah Smith Producer