 The press find these beliefs incompatible, and want to find out why he became a ‘traitor’.Harris is plagued by anxieties over both his actions and his upper-class childhood, and drinks to a state of collapse.Adrian Harris – John Le Mesurier 
 James – Jack Hedley 
 Simpson – Vincent Ball 
 Blake – Neil McCallum 
 Thomas – Jon Laurimore 
 Sir Arthur Harris – Lyndon Brook 
 Lady Emma – Diana Fairfax 
 Michaelov – Richard Marner 
 Duty clerk – Terence Bayler 
 Craig – John Quentin 
 Schoolmaster – John Saunders 
 Young Adrian – Sean Maddox 

Better known for comedic roles, Le Mesurier's casting was a brave move, one which initially concerned the actor who "was very, very scared" that "he wouldn’t be able to pull it off".