John Mills

as Captain Morgan

Ettore Manni

as Luigi Durand de la Penne

Roberto Risso

as Emilio Bianchi

Robert Shaw

as Lieutenant Field

Liam Redmond

as Surgeon Commander Reilly

Dinsdale Landen

as Norris

John Meillon

as Bedford

Patrick Barr

as Rev. Ellis

Moray Watson

as Capt. Turnbull

Gordon Rollings

as Payne

Laurence Naismith

as Admiral

Leonardo Cortese

as Italian Commander