Vince Miller and Fay Forrester ambush two Mob bagmen at a Winnemucca, Nevada, casino, kill one of them, and escape with a briefcase containing green-banded packets of $100 bills. At a rest stop, Fay knocks Vince unconscious with a rock and drives off with the money. In Reno, Nevada, two loan collectors ransack private detective Jack Andrews’s office. They break his finger and tell him to come up with $10,000 by Wednesday. Meanwhile, Fay Forrester arrives in Reno, checks into a motel under the name “Vera Billings,” and counts the money. She is shocked at the staggering sum of $875,000. Fay draws a circle around Jack Andrews’s “Licensed Investigator” advertisement in the newspaper. Elsewhere, Jack combs through files hoping to find clients who still owe him money. His secretary, Terri, suggests he leave the state. Later, Jack lays flowers on his wife’s grave. When Fay arrives at Jack’s office, she explains that her psychotic ex-boyfriend is trying to kill her, but she has no evidence to have him arrested. She believes her only escape is to stage her death, and offers Jack $10,000—half now, and half when the job is done. Desperate for the money, Jack takes the job, and hires his friend, Alan Swayzie, to assist. They acquire a liter of A-negative blood—Fay’s blood type—in a plasma bag, and arrange for fake identification under the name "Vera Billings." Fay checks into a cheap motel as Fay Forrester and flirts with Tim, the young desk manager, to make sure he remembers her. That night, she gambles in a casino and returns to the motel with Jack, who disguises himself in a bulky jacket and cowboy hat. They mess up the motel room, to make it appear as a crime scene, stab holes in Fay's dress, and spill blood on it. Jack wraps her in a bed sheet and carries her to the trunk of her car, conspicuously driving past the manager’s office with his face turned away. Jack takes Fay to another motel, and drives her car into Pyramid Lake, but it does not completely sink. Jack remembers the accident at a similar lake in which he escaped but his wife drowned. Alan Swayzie arrives at Fay’s new motel and discovers that she has checked out and taken a taxicab to the airport, where Jack learns she flew to Las Vegas. In the morning, police arrest Jack and ask if he knows Fay Forrester. Alan arrives to provide an alibi. Lieutenant Sam Hendrix releases Jack, but reminds him not to leave town as he is a murder suspect. Meanwhile, Vince arrives in Las Vegas and reads a newspaper story about Fay’s apparent murder in Reno, and the detainment of Jack Andrews on suspicion. Jack sends Alan Swayzie to Las Vegas to search for "Vera Billings." After Alan leaves, debt collectors arrive at Jack;s office and take the remainder of his money. Vince Miller beats Jack, but in the struggle, Jack escapes. Later, collector “Big Jim” Peterson telephones mobster William Marino in Las Vegas and tells his son-in-law, Stanley “Jonesy” Jones, that the bills he collected from Jack Andrews match the money stolen from Marino’s bagmen, and that Jack has since fled. When Jack telephones Alan from a desert phone booth, he learns that a “Virginia Billingsly” checked into the Las Vegas Hilton. Jack arrives at the hotel's casino and recognizes Fay wearing a red wig as she gambles. At the same time, a local snitch telephones Marino to report a flashy woman with a pile of $100 bills wrapped in a green band. Jack threatens Fay to reveal her real identity, and convinces her to take him to her room. When Jack relates meeting her crazy boyfriend, Fay lies, saying that she fled Reno hoping to draw Vince away from him. She agrees to pay Jack his $5,000 fee, but bagmen “Jonesy” Jones and Sammy burst into the room. Sammy identifies Jack as the man who shot his partner and took their money. He prepares to kill Jack, but Fay shoots him dead and Sammy flees. She and Jack leave Las Vegas in Jack’s white Cadillac. Later, Jack parks next to a Nevada state trooper and demands the truth from Fay, who explains that the two men were picking up skimmed casino money for Marino when Vince Miller robbed them, and that she stole the money from Vince. Jack drives to a remote motel at the far end of Lake Mead, Nevada. There, he and Fay make love during a rainstorm, and afterward he reminisces about a place in Maine where they could hide out. He admits he does not trust her, but needs to work with her to ensure their escape. In the morning, a radio newscaster announces a police manhunt for Virginia Billingsly and Jack Andrews. Roadblocks are set up around the state. Realizing they are trapped, Fay suggests that Jack stage their deaths. “Kill me again,” she insists. Jack plans to stash the money and other provisions on an Indian reservation, then rent a boat and sink it at the lake’s deepest point to fake their deaths. Afterward, they would swim to shore and hike five miles to retrieve the money, and walk another fifteen miles into Arizona. Jack telephones Alan and promises to send him money. He tells Alan he can have everything in his office. When Alan hangs up, he telephones the operator and learns that Jack called from Overton, Nevada. Arriving at Jack’s office, Alan is met by Vince Miller, who beats and tortures him into revealing Jack’s location, then slits Alan's throat. Meanwhile, Jack buys a shovel and drives to an Indian reservation, where he buries the briefcase. He returns to the motel and finds Vince Miller is waiting there. He threatens to kill Jack, but Jack is the only one who knows where the money is buried. Jack proposes splitting the money, but Vince ties him up and puts him into a closet. Vince assaults Fay, but she grabs his gun and shoots him. The shots bring the motel manager pounding on the door. Fay unties Jack and they flee in his Cadillac. However, as they dig up the briefcase, Vince appears. Fay raises Vince’s gun at Jack and admits that she set him up. She shoots him twice, and Jack tumbles off a rock into a lake. Vince tries to finish him off, but two young Native Americans appear and fire rifles into the air. Vince and Fay flee in Jack’s car, leaving Vince’s truck behind. Opening the briefcase, they discover that Jack deceived them and stuffed the case with junk instead of money. Suddenly, police spot Jack’s distinctive car and give chase. As troopers converge on them, Vince tries to escape by driving through several buildings, but crashes into a propane gas tank. Vince and Fay are killed in the explosion. Meanwhile, the wounded Jack is pulled from the water by the two young Natives, who agree to drive him to the reservation hospital, beyond the jurisdiction of the Nevada state police. Later, Jack returns to the site to dig up the money, and the youths drive him to Arizona in Vince's pickup truck as he hides in the back.