Lethal Desire.

When Ava and Julien discover that their new neighbors, Mackenzie and Theo, are swingers, they decide to try out the lifestyle in an effort to spice up their failing marriage. But after Theo turns up dead, Ava becomes the prime suspect in his murder. Desperate to prove her innocence, she searches for the truth even as her own husband comes to distrust her. Ava’s search leads her into the hidden world of swingers, where she encounters jealousy, lies and deceit, before uncovering a secret that’s been living closer to home than she ever realized.