Characters played by Onslow Stevens
Stanley Stanfield
Characters played by Ada Ince
Gloria Barnett
alias Gloria Grant
Characters played by Walter Miller
Wade Barnett
Characters played by James Durkin
Prof. Carl Van Dorn
Characters played by Richard Cramer
Dorgan
Characters played by William Desmond
Newspaper Editor MacDonald
Characters played by J. Frank Glendon
John Cadwell
Characters played by Sidney Bracey
Denny
Characters played by Monte Montague
Badger
Characters played by Edmund Cobb
Kent
Characters played by Beulah Hutton
Sal [Chs.2
3]
Characters played by Don Brodie
Pilot
Characters played by Lee J. Cobb
Roadwork Foreman [Chs. 3
4]
Characters played by Frank Ellis
Nick - Heavyset Thug [Ch. 7]
Characters played by Al Ferguson
Stroud
Characters played by Lois January
John Cadwell's Secretary
Characters played by Tom London
Policeman [Chs. 1
4]
Characters played by Philo McCullough
Smuggling Gang Leader
Characters played by Jack O'Shea
Speedboat Man [Ch. 6]
Characters played by Bud Osborne
Speedboat Man with Binoculars [Ch. 6]
Characters played by William Steele
Henchman