 Ingrid BergmanDr. Constance Petersen | Dr. Constance Petersen |
 Gregory PeckJohn Ballantine | John Ballantine |
 Leo G. CarrollDr. Murchison | Dr. Murchison |
 Michael ChekhovDr. Alexander Brulov | Dr. Alexander Brulov |
 John EmeryDr. Fleurot | Dr. Fleurot |
 Steven GerayDr. Graff | Dr. Graff |
 Paul HarveyDr. Hanish | Dr. Hanish |
 Erskine SanfordDr. Galt (uncredited) | Dr. Galt (uncredited) |
 Norman LloydMr. Garmes | Mr. Garmes |
 Donald CurtisHarry | Harry |
 Rhonda FlemingMary Carmichael | Mary Carmichael |
 Bill GoodwinHouse detective | House detective |
 Art BakerDet. Lt. Cooley | Det. Lt. Cooley |
 Regis ToomeyDet. Sgt. Gillespie | Det. Sgt. Gillespie |
 Wallace FordHotel masher | Hotel masher |
 Jean AckerMatron (uncredited) | Matron (uncredited) |
 Irving BaconRailway Gateman (uncredited) | Railway Gateman (uncredited) |
| RRichard BartellTicket Taker (uncredited) | Ticket Taker (uncredited) |
| HHarry BrownGateman (uncredited) | Gateman (uncredited) |
| JJoel DavisJohn Ballantine as a Boy (uncredited) | John Ballantine as a Boy (uncredited) |
 Jacqueline deWitNurse (uncredited) | Nurse (uncredited) |
 Edward FieldingDr. Anthony Edwardes (uncredited) | Dr. Anthony Edwardes (uncredited) |
 Alfred HitchcockMan Leaving Elevator (uncredited) | Man Leaving Elevator (uncredited) |
 Teddy InfuhrJohn Ballantine's Brother (uncredited) | John Ballantine's Brother (uncredited) |
 Victor KilianSheriff (uncredited) | Sheriff (uncredited) |
 George MeaderHallett - Railroad Clerk (uncredited) | Hallett - Railroad Clerk (uncredited) |
 Matt MoorePoliceman at Train Station (uncredited) | Policeman at Train Station (uncredited) |
 Constance PurdyDr. Brulov's Housekeeper (uncredited) | Dr. Brulov's Housekeeper (uncredited) |
 Addison RichardsPolice Captain (uncredited) | Police Captain (uncredited) |
| JJanet ScottNorma Cramer (uncredited) | Norma Cramer (uncredited) |
