Piano player Al (Tom Neal) is bitter about having to work in a New York nightclub. After his girlfriend Sue (Claudia Drake) leaves to seek fame in Hollywood, he decides to join her. With little money, he has to hitchhike his way across the country. In Arizona, bookie Charles Haskell Jr. (Edmund MacDonald) gives him a ride in his convertible. Haskell has Al pass him pills several times along the way. That night, Al is driving while Haskell sleeps, when a rainstorm forces Al to pull over to put up the top. Unable to rouse Haskell, Al opens the passenger-side door. Haskell falls out and strikes his head on the ground. Al then realizes the bookie is dead. Fearful that the police will believe he killed Haskell, Al dumps the body off the side of the road, takes Haskell’s money, clothes and identification, then drives away. After spending the night in a motel, Al picks up another hitchhiker, Vera (Ann Savage), at a gas station. By sheer bad luck, it turns out that the femme fatale had also been picked up by Haskell earlier. She scratched him deeply in the arm and got out after he tried to become too friendly. When Al identifies himself as Haskell, she blackmails him by threatening to turn him in.
In Hollywood, they rent an apartment, posing as Mr. and Mrs. Haskell to provide an address when they go to sell the car. However, Vera learns from a newspaper that Haskell’s wealthy father is near death and looking for his son, who ran away as a youth after accidentally injuring his friend. Vera demands that Al impersonate Haskell, but Al balks at this notion, pointing out that he knows nothing about the dead man. Back in the apartment, Vera gets drunk, and they begin arguing. She threatens to call the police, running into the bedroom with the telephone and locking the door. She falls into a stupor on the bed, with the telephone cord tangled around her neck. Al tries to break the cord. Then, when he breaks down the door, he sees that he has accidentally strangled her. He goes hitchhiking again, but is picked up by the police.