Plot
In 1941 Los Angeles, private detective Philip Marlowe is hired by recently paroled felon "Moose" Malloy to find his old girlfriend Velma Valento, whom he has not seen in seven years while he has been in prison. Malloy goes to ground after killing the new owner of the nightclub where Velma used to work. Using a photo supplied by Velma's old nightclub friend Tommy Ray, Marlowe traces her to an insane asylum in Camarillo, but when he breaks the news to Malloy, he discovers that he had been given a photo of a different woman.
Meanwhile, a man named Lindsay Marriott hires Marlowe to accompany him to a rendezvous where he is to pay $15,000 ransom for the return of a valuable fei tsui jade necklace stolen from an unnamed female friend. At the location of the pay-off, Marlowe is knocked unconscious by an unseen assailant and when he recovers, the police are at the scene and Marriott has been killed. At the police station Marlowe is told that Malloy has fled to Mexico and is warned to stop looking for Velma.
Deciding to investigate Marriott's death, Marlowe is given a lead on a collector of fei tsui jade named Baxter Grayle, who is a judge and a powerful figure in Los Angeles. At Grayle's mansion he meets Grayle and his wife, the much younger and very seductive Helen. Helen wants to know who killed Marriott, whom she had known for years, and offers to pay Marlowe to find out. Marlowe is abducted at his office and brought to the brothel operated by Frances Amthor, a notorious madam. Amthor mentions Malloy, then beats and drugs Marlowe. After waking from his heroin-induced stupor and discovering the body of Tommy Ray, Marlowe overpowers the guard Cowboy and confronts Amthor, but she is uncooperative. Jonnie, an employee of Amthor, shoots her when she beats one of her girls for being with Jonnie. Marlowe flees (along with everyone else in the house) and makes it to his friend Georgie's house.
A few days later, Helen telephones Marlowe at his office and arranges to meet him at a party later that night. At the party, Marlowe talks to underworld figure Laird Brunette, who pays Marlowe $2,000 to arrange a meeting with Malloy. Later Marlowe meets Velma's old nightclub friend Jessie Florian, who says Velma has contacted her and wants to contact Malloy. Marlowe meets with Malloy at Georgie's house, where Velma telephones and arranges to meet him. Marlowe drives him to the motel where Velma is supposedly waiting. Instead, they are ambushed by two gunmen, whom Marlowe kills in a shootout.
Marlowe and the police find Jessie Florian murdered. Marlowe suggests to his police friend Nulty that whoever used Florian to set up Malloy at the motel also got Tommy Ray to supply the fake photograph to send him off on a wild goose chase. Marlowe is convinced that Brunette knows what is going on, so he and Malloy sneak aboard Brunette's gambling boat and confront him. Helen appears and it is revealed she is Velma, a former prostitute under Amthor, who married Baxter Grayle without his knowing about her background. Velma has been working with Brunette to kill off anyone who knows her real identity to protect Brunette's hold over Judge Grayle.
In spite of Marlowe's warnings to Moose, Velma shoots Malloy and in turn Marlowe shoots her. As Nulty and the police arrive, Marlowe leaves and returns to his hotel room. He decides to give the $2,000 that he had received from Brunette to Tommy Ray's widow and young son, both of whom he had met earlier.
