Eric Portman
— Dr. David Sorel
Ian Hendry
— Paul Du Pre
Peter Wyngarde
— Hugo de Croissillon
Jeanette Sterke
— Eliane de Croissillon
Philip Locke
— Vedoni
Michael Coles
— Armidal
Roger Delgado
— Dr. Si Cada
Wolfe Morris
— Lieutenant Vinh
Patrick Barr
— General Palice
Anne Blake
— Francesca
Zoe Randall
— Dr. Marianne Lagny
Nádasi Myrtill
— Maria
Frank Gatliff
— President of the Court