 Rondo HattonHal Moffet AKA 'The Creeper' | Hal Moffet AKA 'The Creeper' |
 Tom NealClifford Scott | Clifford Scott |
 Jan WileyVirginia Rogers Scott | Virginia Rogers Scott |
 Jane AdamsHelen Paige | Helen Paige |
 Donald MacBridePolice Captain M. J. Donelly | Police Captain M. J. Donelly |
 Peter WhitneyPolice Lieutenant Gates | Police Lieutenant Gates |
| FFred CobyYoung Hal Moffet | Young Hal Moffet |
| JJanelle Johnson DolenzJoan Bemis (as JaNelle Johnson) | Joan Bemis (as JaNelle Johnson) |
| MMary Ann BrickerMary Ann Obringer (uncredited) | Mary Ann Obringer (uncredited) |
 Tristram CoffinPolice Lieutenant / voice of radio announcer (uncredited) | Police Lieutenant / voice of radio announcer (uncredited) |
 Joseph CrehanPolice Commissioner Salisbury (uncredited) | Police Commissioner Salisbury (uncredited) |
 John HamiltonProfessor Cushman (uncredited) | Professor Cushman (uncredited) |
 Frank O'ConnorPoliceman at Helen's Apartment (uncredited) | Policeman at Helen's Apartment (uncredited) |
 Beatrice RobertsNurse (uncredited) | Nurse (uncredited) |
 Charles WagenheimPawnbroker (uncredited) | Pawnbroker (uncredited) |
| WWilliam RuhlPoliceman at Helen's Apartment (uncredited) | Policeman at Helen's Apartment (uncredited) |
 James NolanPolice Dispatcher (uncredited) | Police Dispatcher (uncredited) |
 Oscar O'SheaMr. Haskins - Grocer (uncredited) | Mr. Haskins - Grocer (uncredited) |
 Patrick McVeyDetective at Helen's Apartment (uncredited) | Detective at Helen's Apartment (uncredited) |
| WWarren JacksonJeweler (uncredited) | Jeweler (uncredited) |
