Kirk Alyn

Blackhawk

Carol Forman

Laska

Carol Forman

Chuck

John Crawford

Chuck

Michael Fox

Mr. Case

Don C. Harvey

Olaf

Rick Vallin

Stan / Boris

Zon Murray

Bork

Nick Stuart

Cress

Marshall Reed

Aller

Pierce Lyden

Dyke

William Fawcett

Dr. Rolph [Chs. 4-7]

Rory Mallinson

Hodge [Chs. 11-14]

Frank Ellis

Hendrickson [Chs. 1-2, 4, 8-9]

Frank Gerstle

Dawson [Chs. 7-8]

Knox Manning

Narrator (voice)