A spotlight on true-crime stories of love affairs gone wrong, spouses driven to kill and other crimes of passion.

In Washington, a husband goes missing; killer swingers in the U.K.

In Las Vegas, a killer leaves a calling card; a car's trunk holds something shocking in Melbourne, Australia.

In Reno, someone makes a plan to kill a politician; an office romance gets out of hand and leads to a woman's disappearance in Coventry, England.

An adulterous husband trains his lover in the art of killing in Daytona Beach, Fla.; a woman falls in and out of love in Sydney, Australia.