Christopher Cazenove

as Aristotle

as Professor Higgins

as Athos (2 episodes)

as The Customer

as Lord Peter

as Andrew Fontaine

as DAC Row Colemore (12 episodes)

as John Thatcher

as Jerome

as President of Clarion

as Thrask (1 episode)

as Melchoir

as Elliott Spencer

as Rob Denton (1 episode)

as Nigel Poole (1 episode)

as Claire's Colleague

as Guy Latimer (2 episodes)

as Milo

as Jonathan Ainsley (2 episodes)

as Palmer

as Edward

as Larry (1 episode)

as Michael Trent (12 episodes)

as William Root