A brilliant central performance by William Hurt as a Florida lawyer caught up in an obsessive affair with Kathleen Turner's married woman which leads to them plotting the murder of her husband. Writer/director Lawrence Kasdan clearly used Double Indemnity as a blueprint but adds some nifty twists and turns, not to mention a high sexual charge to the proceedings. There are some notable supporting performances from Ted Danson, Richard Crenna and Mickey Rourke too. A marvellously "80s" thriller, and that's intended as a compliment.

I'm not sure why you find the ambiguous ending troubling, george4mon:

She switched identities with the other girl, killed her, put the dead body in the boathouse, and had some sort of trigger mechanism to set off the fire bomb. She (Mary Ann Simpson) gets a clean break because the dental records of the dead woman do match up against the real Matty Walker. And her high school dream --- to be rich and live in an exotic land --- comes to fruition.

This movie is not boring.