Night Fire (1994)

Lydia and Barry are unhappily married. They live on a very expensive, but remote ranch. She is a powerful businesswoman yet neglectful wife. Poor Barry turns to kinky sex to combat her frigidity. A swinging couple, Gwen and Cal suddenly appears at the door claiming their car broke down. They were really hired by Barry to warm up his wife. Plenty of fondling ensues, but Lydia remains unmoved. Barry starts getting uglier.