Undercover vice squad detective Tom Howarth goes missing while investigating the murder of a prostitute. His wife Lois and his best friend Matt, also detectives, set out to search for him, but end up falling in love with one another.

Post-grad Joshua Penny investigates the murder of his mother in Brighton, who was killed after witnessing another murder. He delves into the local underworld to find the real killer, as police suspect his father.

When DS Mike Hazard disappears, his wife Susie tries to find him, and discovers... another wife. They team up to search for him.