Stephen Boyd

Grant

Raquel Welch

Cora

Edmond O'Brien

General Carter

Donald Pleasence

Dr. Michaels

Arthur O'Connell

Col. Donald Reid

William Redfield

Capt. Bill Owens

Arthur Kennedy

Dr. Duval

Jean Del Val

Jan Benes

Barry Coe

Communications Aide

Ken Scott

Secret Service

Shelby Grant

Nurse

James Brolin

Technician

Brendan Fitzgerald

Wireless Operator

Brendon Boone

Military Policeman (uncredited)

James Doohan

Dr. Sawyer (Hypothermia technician) (uncredited)

Kenneth MacDonald

Henry - Heart Monitoring (uncredited)

Christopher Riordan

Young Scientist (uncredited)