Early one morning, homicide detective Bert Rawley sneaks up to a cabin in a California auto court and apprehends his best friend, policeman Ray Patrick inside. Ray, a well-respected detective, apologizes and explains why he ran away with convicted killer Eden Lane: Months earlier, in Los Angeles, Ray receives a call to investigate the murder of businessman Fred Deane. Deane’s face and hands are burned beyond recognition, and Miss Farrell, the landlady who found him, intimates that Deane’s girl friend, Eden, was involved. Ray goes to the nightclub where Eden works as a singer, and there meets her roommate, photographer Patsy Flint. The cunning Patsy tries to hinder Ray's investigation, but upon examining their apartment, he discovers that Eden has fled on a nothern-bound bus. Ray soon learns that Eden disembarked at Merced and, after driving there, finds her at Deane’s moutain lodge. Due to a snowstorm, Ray and Eden are trapped overnight, and as they talk, Ray is uncertain that the quiet, unassuming Eden could have committed murder, although she admits to her burgeoning affair with Deane, and that she struck him with a heavy figurine during an argument. Eden left the apartment before Deane regained consciousness, and fears that he may have fallen into the fireplace and died. After a speedy trial, during which little information about Deane is produced, Eden is found guilty. Ray is assigned to escort Eden to prison, and during their train ride, he is again impressed by Eden’s demeanor. While they are stopped briefly at Lindaville, Eden is shocked to see Deane standing on the platform, and Ray, persuaded by her insistence that she is innocent of the crime for which she has been convicted, jumps off the train with her. Determined to solve the mystery, Ray agrees to stay in Lindaville for one week, but orders Eden not to escape. They then check into the auto court, and the following day, while he is driving through town, Ray is surprised to see Patsy walking by. Sneaking into her hotel room, Ray discovers $5,000 hidden in her suitcase and takes the money. The next day, Ray is baffled that there is no report of the theft and realizes that Patsy could not have come by the money honestly, or else she would have reported it missing. Desperate for a lead, Ray plays a hunch and visits the Abbott Ceramics factory, which is owned by Abbott and his socially prominent wife Beatrice. Ray spots a photograph of a factory banquet and decides to steal it on the “long chance” that Deane is in it. Ray hides in a closet and takes the photo late that night, but is attacked by an unseen assailant. He manages to escape and return to the motel, but Eden does not recognize anyone in the picture. Ray is discouraged, as he has fallen in love with Eden, but when he offers to run away with her, she urges him to keep investigating. Ray spends the next day fruitlessly searching for clues, and when he returns home, discovers that Eden has vanished. With his story completed, Ray begs Bert for another twenty-four hours to continue his search, and Bert reluctantly acquiesces. They then follow Patsy to a church service, after which she returns to her hotel. Later, when the detectives check Patsy’s room, they discover that she has been murdered. Finding an unsigned note inside Patsy’s hymnal, which instructed her to meet the writer at a later time, Bert and Ray go to the ceramics factory, where they find Abbott working. Noticing that Abbott’s ring matches the bruise on Ray’s face, Bert accuses him of attacking Ray. When the men assert that, according to Abbott’s bank records, he recently withdrew $5,000, the exact sum found in Patsy's suitcase, he denies their charges that Patsy was blackmailing him. Bert and Ray leave when Beatrice arrives, but overhear her upbraiding her husband for damaging her family’s reputation. Soon after, Bert learns that Eden surrendered in an attempt to clear Ray of charges of collusion. Ray then telephones Miss Farrell, asking her to come to Lindaville. Miss Farrell arrives on the same train boarded by Abbott and his wife, who are leaving on vacation, but is able to identify Abbott as Deane. Bert and Ray jump aboard, and while Beatrice sees them and hides in the corridor, Abbott admits to the detectives that he is Deane and that he met Eden during a business trip to Los Angeles. Abbott explains that he began seeing Eden and became so infatuated with her that he hired a private detective named Mike to follow her. Upon receiving a blackmailing letter, Abbott assumed that Eden had learned his true identity, but when he confronted her about it, she denied it and in the heat of the moment, struck him over the head. After regaining consciousness, Abbott killed the private detective and burned his body to prevent further blackmail attempts. To Abbott’s surprise, Patsy was the real blackmailer, and when she arrived in Lindaville, she demanded money. Abbott paid her, and was prepared to give her more money after she was robbed, but swears that he did not kill her. When the detectives show him the note in Patsy’s hymnal, Abbott recognizes the handwriting as Beatrice’s and, realizing that Beatrice must have killed Patsy to keep her quiet, runs out of the compartment just as she throws herself off the train to her death. Later, in Los Angeles, Bert informs Ray that although he will not be prosecuted, his days as a policeman are over. Ray is greatly cheered, however, when Eden arrives and Bert accompanies them to the marriage bureau.