A homeless man finds human limbs wrapped in black bin bags. It's the start of a trail of forensic clues that will eventually lead police to one of London's most shocking serial killers.

A dog walker discovers the body of a girl lying in woodland. 13-year-old Lucy McHugh has been stabbed 27 times in a brutal, calculated attack.

Police get a frantic call from a man saying his wife has been killed. The caller is Dr Dirk Greineder, a respected Harvard physician, who has blood on his clothes and shoes.

On the 10th November, 2000, a bouncer at the Paradise Bar in New Cross, London is rushed to hospital. George Napier has been stabbed multiple times and mauled by a dog.

In Nov 1993, the small community of Hambleton in Leicestershire is shocked when an elderly couple mysteriously go missing.

A father of six is missing, presumed murdered after a night out with violent criminals. Police have their suspects, but without a body, it’s an uphill task to secure a conviction.

In 1998, detectives are certain that Joseph Romano is responsible for killing his wife. But with no trace of her body, they are struggling to build a case for the prosecution.

A single mother is found dead in the woods. Her boyfriend is the main suspect but with no witnesses or DNA evidence, police call on two forensic investigators to solve the crime.

A woman’s body is found in a suitcase in a car park at Heathrow Airport. Detectives have no idea they’re about to launch a decade long investigation, across multiple continents.