On a frozen Bristol night, a missing young woman's walk home is captured on flickering CCTV. When her body is found, the hunt for a killer turns a quiet street into a labyrinth of suspicion, where the most dangerous person may be the one living next door.

The suspicious deaths of two elderly neighbors draw attention to a charming young churchwarden. When investigators uncover his attempts to use romance and religion to seduce them into signing over their estates, a race begins to discover whether he is a killer.

When the murder of a young woman points police to a quiet church handyman, detectives uncover a serial killer hidden in plain sight for decades, linked to multiple killings across the U.K.