20/20 Britain's Most Notorious Crime Investigations

A Greek paradise becomes hellish after a British toddler vanishes without a trace. Their search leads his family into the murky world of child-trafficking, suspected burial sites and a prison confession – but can they discover the truth?

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.

The British Royal Family is linked to scandal when a former aide goes on the run after her boyfriend is murdered. When police find her, she makes explosive allegations of abuse by him. Police delve into the couple's secrets to ask if she murdered in cold blood?

A chilling 999 call captures two men in their final moments during a deadly high-speed car chase. CCTV leads police to a viral mother-daughter TikTok duo, exposing dark family secrets, a deadly ambush plot and a ruthless obsession with image.