Barrie Ingham as Basil of Baker Street / Bartholomew (voice)

Vincent Price as Professor Ratigan (voice)

Val Bettin as Dr. David Q. Dawson / Thug Guard (voice)

Susanne Pollatschek as Olivia Flaversham (voice)

Candy Candido as Fidget (voice)

Diana Chesney as Mrs. Judson (voice)

Eve Brenner as The Mouse Queen (voice)

Alan Young as Mr. Flaversham (voice)

Basil Rathbone as Sherlock Holmes (voice)

Ellen Fitzhugh as Bar Maid (voice)

Walker Edmiston as Citizen / Thug Guard (voice)

Wayne Allwine as Thug Guard (voice)

Tony Anselmo as Thug Guard (voice)

Frank Welker as Toby the Dog / Felicia the Cat (voice) (uncredited)

Laurie Main as Dr. Watson (archive sound)

Shani Wallis as Lady Mouse (voice)

Melissa Manchester as Miss Kitty Mouse (voice) (uncredited)