While hunting a fox who caused their truck to swerve and crash, three men make an astonishing find in the wintry Minnesota woods. Dimwitted Jacob, his belligerent buddy Lou and Jacob's younger brother and reluctant partner-in-crime Hank discover a crashed airplane covered in snow. Inside are the dead pilot and four million dollars in cash. Hank wants to alert the authorities, the others want to keep it. Hank yields on one condition: that he keep the money until the plane is discovered in the spring thaw. If no one comes after the money, the three will divide the cash.
Despite swearing the others to secrecy, Hank spills all to his wife Sarah. Hank obeys her and returns some of the money to the plane to avert any suspicion. On lookout duty, Jacob panics and hits a farmer named Dwight who's hunting a fox. Hank prepares to dispose of the body but Dwight regains consciousness. Hank smothers Dwight and stages the death as a snowmobile accident despite Jacob's protests.
Unemployed Lou threatens to tell the sheriff the truth about Hank killing Dwight unless he gets his share of the money now. Sarah tells Hank to frame Lou for Dwight's death. Jacob reluctantly agrees to double-cross his friend and gets Lou to fake a confession to Dwight's murder. Hank reveals he secretly recorded Lou's confession. Lou threatens to kill Hank, so Jacob shoots Lou dead. Hank kills Lou's wife Nancy makes it look like Lou did it.
The sheriff, Carl, believes Hank's and Jacob's cover story. He's got more important things on his mind, like helping visiting FBI agent Baxter. After Jacob stupidly revealed he heard the sound of a sputtering airplane engine, Carl asks Jacob and Hank to help him and Baxter look for a missing plane. Sarah tells Hank Baxter isn't really an FBI agent, he's one of two criminal brothers who kidnapped and ransomed an heiress. The other brother piloted the doomed plane. Yet Hank joins the search for the plane. Carl discovers the downed plane but is shot dead by Baxter, who really is one of the kidnappers. Baxter assumes Hank won't kill him in cold blood, but he doesn't know the practice Hank's been getting.
Jacob won't go along with Hank's cover story. Consumed by guilt, he asks Hank to kill him with Baxter's gun or he'll commit suicide. Hank kills Jacob and gets away with it. FBI agents inform Hank that they recorded many serial numbers of the ransom bills. Hank returns home and Sarah can't prevent him from burning all the money.