When two young men are found dead in London, the police blame their deaths on overdoses. Their loved ones are unconvinced and try to find out the truth.
Another man’s body is found in the same place in London, but again the police rule it an overdose. Meanwhile, the suspicions of the previous two men’s families continue to rise.
A fourth man’s body is found, and the victims' families want answers. Stephen Port is arrested, but securing a guilty conviction for the murder of all four men is far from certain.
Four Lives airs Monday 3rd-Wednesday 5th January at 9pm on BBC One.