Bill Travers

Joe Ryan

William Sylvester

Sam Slade

Vincent Winter

Sean

Christopher Rhodes

McCartin

Joseph O'Conor

Prof. Hendricks

Bruce Seton

Prof. Flaherty

Martin Benson

Dorkin

Maurice Kaufmann

Radio Reporter

Basil Dignam

Admiral Brooks

Barry Keegan

Mate

Tommy Duggan

First Naval Officer

Howard Lang

First Colonel

Dervis Ward

Bosun

Mick Dillon

Gorgo

Nigel Green

Bulletin Announcer (Uncredited)

Eugène Lourié