Graham Hainsworth (1 episode)
Uncle Millard
Bernard Thatch (2 episodes)
King Salazar (voice)
Basil Rathwood
Mr. Waltham (2 episodes)
Horace Walpole (6 episodes)
British Reporter
Dr. Campbell (1 episode)
Dr. Menard (1 episode)
Cats' Producer (1 episode)
Dr. McMerlin
Commander (voice) (1 episode)
Duke Stone (21 episodes)
Dr. Whitcomb (3 episodes)
Judge In Heaven
Dr. Tiberius Scott
Harvey Wilks
Reginald Harrington (1 episode)
Hal Conway (8 episodes)
Dr. Henry Davenport, the Invisible Man (voice)
Anton / Kreeger Paulovitch
Cheshire
Sir David Tushingham (2 episodes)
Judge (voice) (1 episode)
Count (voice)
Hector Paradiso (2 episodes)
Father Rosetti
Fenwick (1 episode)
Captain Oliver (1 episode)
"Center" Instructor
Lord Malcolm Billings
Phillip Barbay
Morgan (1 episode)
William Troubshaw (1 episode)
Gordon Chumley (1 episode)
Patrick Burke (1 episode)
McDougall