Peter Firth as Robert 'Bobby' Stewart

George Sewell as Henry Stewart

Patrick Allen as Insp. Cook

Derek Newark as Mercer

Dudley Sutton as Finch

Barry Jackson as Wheeler

Christopher Malcolm as Jock

Edwin Richfield as

Richard Wattis as Sir Hilary Stanton

Ambrosine Phillpotts as Lady Truesdale

Allan Cuthbertson as Gus Ashley

Arthur Hewlett as Benjy

Spencer Banks as Charlie Todd

Cynthia Lund as Susan Stewart

Candace Glendenning as Elizabeth (uncredited)

Robin Langford as Peter Pitt

Tom Bowman as

John Savident as Steward

Mark Edwards as Whiteman

Patrick McAlinney as Junkman

Andrew McCulloch as Billy

George Woodbridge as PC Andrew

Patrick Holt as Steward

Maggie Hanley as Mrs. Maggie Stewart

George Innes as Insp. Timothy