Cmdr. Don Winslow

Don Terry

Acting

Mercedes Colby

Claire Dodd

Acting

Spencer Merlin

John Litel

Acting

Lt. Red Pennington

Walter Sande

Acting

Misty Gaye

Anne Nagel

Acting

Mike Splendor

Wade Boteler

Acting

John Blake

Ben Taggart

Acting

Paul Barsac

John Holland

Acting

Henchman Corley

Lane Chandler

Acting

Henchman Spike

Ethan Laidlaw

Acting

Seaman Chapman

Peter Leeds

Acting

Henchman Prindle

Robert Barron

Acting

The Scorpion

Kurt Katch

Acting

Gang Radioman Barker

Ray Teal

Acting

Lt. Cdr. Grady

Dirk Thane

Acting

Admiral Warburton [Ch. 1]

Herbert Rawlinson

Acting

The CINCUS [Ch. 1]

Samuel S. Hinds

Acting

Capt. Holding [Ch. 1]

Kenneth Harlan

Acting

Enemy Sub Capt. Tranker [Ch. 1]

Arthur Loft

Acting

Capt. Fairfield, of the "Batavia" [Chs. 1-2]

Paul Scott

Acting

Tangita Jim [Chs. 2, 10]

Jerry Mandy

Acting

Capt. Sanders, of the "Tarleton" [Chs. 3-4]

Heenan Elliott

Acting

Saboteur Kramer [Chs. 3-4]

Paul Bryar

Acting

Lead Henchman at Mill [Ch. 5]

Edward Hearn

Acting

Native Henchman at Mill [Ch. 5]

Iron Eyes Cody

Acting

Witch Doctor Koloka [Chs. 6-7]

Frank Lackteen

Acting

Sub Capt. Jackson [Chs. 7, 9]

Guy Kingsford

Acting

Sam Munn, henchman [Ch. 8]

Ken Terrell

Acting

Henchman Butch [Ch. 8]

Jack Rockwell

Acting

Gang Chemist Taylor [Chs. 8-9]

Irving Mitchell

Acting

Taylor's Lab Assistant [Ch. 8]

Eddie Polo

Acting