Kerwin Mathews as Jonathon Standing

Christopher Lee as Captain LaRoche

Andrew Keir as Jason Standing

Glenn Corbett as Henry

Michael Ripper as First Mate Mack

Peter Arne as Bosu'n Hench

Marla Landi as Bess Standing

Oliver Reed as Pirate Brocaire

Jerold Wells as Penal Colony Master

Dennis Waterman as Timothy Blackthorne, the boy

David Lodge as Smith

Jack Stewart as Godfrey Mason

Marie Devereux as Maggie Mason (uncredited)

Emile Stemmler as A villager (uncredited)

Bert Simms as Old Townsman (uncredited)

Denis Shaw as Silver (uncredited)

John Roden as 2nd Settler (uncredited)

Ernie Rice as Pirate (uncredited)

Keith Pyott as Silas (uncredited)

Dido Plumb as Prisoner (uncredited)

Michael Peake as Kemp (uncredited)

Michael Mulcaster as Martin (uncredited)

Desmond Llewelyn as Tom Blackthorne (uncredited)

Don Levy as Carlos (uncredited)

George Hilsdon as Penal Colony Guard (uncredited)

John Collin as Lance (uncredited)

Bill Brandon as Pirate (uncredited)

Jim Brady as Pirate (uncredited)

Ronald Blackman as Pugh (uncredited)

Richard Bennett as Seymour (uncredited)

John Bennett as Penal Colony Guard (uncredited)

Diane Aubrey as Margaret Blackthorne (uncredited)