Duncan Richards
Diana Farnsworth
Louis Ashe
Dr. Blackton [Ch. 11]
Dr. Chambers [Chs. 1-2, 8]
Prof. Van Wyck
Anderson [Chs. 1-4]
Maxwell
Prof. Parker (as Joe Forte)
Count Fator [Chs. 11-12]
Wilson [Ch. 1]
Henchman Stricker [Chs. 4, 7, 9]
Henchman Harte [Chs. 6-7]
Bain
Snyder [Chs. 1-2] / Zane [Ch. 8]
Cross - Apartment Thug [Chs. 11-12]