Body Heat

Body Heat is a 1981 American neonoir erotic thriller film written and directed by Lawrence Kasdan. It stars William Hurt, Kathleen Turner and Richard Crenna, and features Ted Danson, J.A. Preston, and Mickey Rourke. The film was inspired by Double Indemnity and Out of the Past.

During a particularly intense Florida heatwave, inept lawyer Ned Racine William Hurt begins an affair with Matty Kathleen Turner, the wife of wealthy businessman Edmund Walker Richard Crenna. They go to great lengths to keep their affair a secret, but Ned carelessly propositions an old school friend of Matty, Mary Ann Simpson Kim Zimmer, thinking she was Matty. Matty soon makes it clear to Ned that she wants to leave Edmund but also wants his money, explaining that a divorce would leave her with very little due to their prenuptial agreement. Racine suggests the only option is to kill Edmund. While planning the murder, Ned consults one of his shadier clients, Teddy Lewis Mickey Rourke, an expert on incendiary devices, who supplies him with a bomb.Racine drives to the Walker estate at night to kill Edmund. He places the body in an abandoned building in which Edmund had a business interest, and uses the incendiary device to make it look like he died during a botched arson job. Ned is contacted by Edmunds lawyer about a new will that Racine supposedly drew up on Edmunds behalf, which was witnessed by Mary Ann Simpson. The new will is so poorly prepared it is declared null and void, resulting in Matty inheriting the entire fortune. Matty later admits to Ned that she forged the will. ........

Source: Wikipedia