Upcoming episodes, programme details and where to watch over the next seven days. All times are UK time.
2/2. The detectives investigate the identity of the mother and child in the stolen photos - are they connected to the first mother and daughter? Contains distressing scenes.
1/2. A woman leaves her husband for a troubled musician, resulting in tragedy. As detectives investigate, they uncover thwarted ambition and jealousy. Contains distressing scenes.
2/2. Zailer and Waterhouse are still on the hunt for the killer. Uncovering the couple's past, they discover a history of murderous jealousy. Contains distressing scenes.
1/2. A mother and daughter are found dead at home, apparently a case of murder-suicide. Yet detectives suspect the husband is not all he seems. Contains distressing scenes.