Weybread, Suffolk: Peter and Sylvia Stuart, an elderly couple recently moved from town to country soon go missing, and then in woodland, a body is found.
Clydebank, West Dunbartonshire, Scotland: When 15-year old Paige Doherty is killed on her way to her hairdressing job, residents begin to regard each other with suspicion and start to feel unsafe in their own community.
Newry, Northern Ireland: 81-year grandmother Maire Rankin is found beaten to death in her own home. As she was an extremely popular local figure, it is a mystery why anybody would want to harm her.