Most killers know their victims, but there has been an alarming rise in 'stranger murders', and these are the shocking stories of people killed by someone they had never previously met.
Tashan Daniel: Twenty-year-old Tashan Daniel was waiting for a train to take him to a football match when a fateful encounter on the platform changed everything.
Yingying Zhang: After missing her bus, Yingying Zhang is offered a lift by a man posing as a policeman. This fateful encounter would lead to her horrific murder.
Jeralee Underwood: The story of 11-year-old Jeralee, who was lured into the car of James Edward Wood - a man with no reason to harm but a strong desire to kill.
Amber Dubois & Chelsea King: Two teenage girls have the misfortune of crossing paths with a cold-blooded killer, one year apart.
As Robin Chard makes his way home to his wife, he crosses paths with two men who carry out a brutal and unprovoked attack on him.
While walking her dogs at a local beauty spot, Debbie Buxton is killed in a frenzied and unprovoked attack by David Bond.
In 2015, a bizarre home invasion leaves 69-year-old pastor Ron Browning dead when he opens his door to 19-year-old Camille Brown.
When Matthew accepts a ride home from two men, his case makes headline news when he is tortured and left for dead in a hate-fuelled attack.
19-year-old Celine accepts a ride from a lorry driver, but never makes it to her destination. Ten days later, her body is found. (S1, ep 9)
After Dark: India Chipchase: After a night out, 20-year-old India is lured to her death by man who was overheard telling her he would 'get her home safe'.