Penance is a three-episode drama film first broadcast by Britain's free-to-air Channel 5.
Rosalie and Luke are a well-to-do estranged couple whose son was found dead in Thailand.
They are introduced to Jed, whose parents died in an auto accident, and are sympathetic.
Jed inveigles his way into the household as a gardener, then takes over the son's bedroom.
She lures him to a remote location where, after a scuffle involving her husband, she stabs him with a kitchen knife.