Four couples set off on a three day, self-drive river cruise. Brett and Crystal, both in relationships with other partners, discover a deep attraction for each other. This does not go unnoticed, and anger and resentment begin to simmer.
On the last morning, the group is shocked to find Crystal missing. A thorough search fails to find her. She has disappeared without a trace.
Three years pass, and a body is found. Under the direction of...