The Orange County Sheriff's Office has been more than just a job to Sergeant Dan Van Huelin over the years. He's found four ex-wives, a fifth wife, and a lover among the department's office staff and deputies.

Decades spent in law enforcement have exposed Dan to the best and worst in people-sometimes at the same time. Often it seems that circumstances and not morality determine whether a person acts like a good citizen or a lawbreaker, whether a man remains faithful to his wife, and how said wife reacts when she finds a love letter from her rival.

In Lulu Darling's case,...