- Judd Holdren
- Larry Martin
- Aline Towne
- Sue Davis
- Wilson Wood
- Bob Wilson
- Lane Bradford
- Marex
- Stanley Waxman
- Dr. Harding
- John Crawford
- Roth
- Craig Kelly
- Mr. Steele
- Leonard Nimoy
- Narab
- Tom Steele
- Walker [Ch. 3] / Truck Driver [Ch. 8]
- Dale Van Sickel
- Telegrapher [Chs. 1, 10]
- Roy Engel
- Lawson - Boat Charter Operator [Ch. 3]
- Jack Harden
- Kerr
- Paul Stader
- Fisherman [Ch. 7]
- Gayle Kellogg
- Dick - Rocketship Pilot
- Jack Shea
- Rocketship Guard [Ch. 2]
- Robert Garabedian
- Elah - Zombie Pilot
- Frank Alten
- Second Train Heavy [Ch. 1]
- Roy Barcroft
- Central Control Radio Operator [Chs. 1, 11] / Ross [Ch. 4] (voice) (uncredited)
- Ray Boyle
- Henchman
- Davison Clark
- Ferndale Policeman [Ch. 5]
- Floyd Criswell
- Ferndale Policeman [Ch. 5]
- John Daheim
- Henchman
- Paul Gustine
- Plane Pilot [Ch. 4]
- John Mack
- Gomez - Siding Switchman [Ch. 1]
- George Magrill
- First Train Heavy [Ch. 1]
- Henry Rowland
- Dapper Gangster on Plane [Ch. 4]
- Robert Strange
- Kettler - Sub Quartermaster [Ch. 7]
- Ken Terrell
- Henchman
- Norman Willis
- Tarner - Sub Captain [Ch. 7]
- Clifton Young
- Ross - Smuggler Boss [Ch. 4]
