In Brixton, south London, a man's body is found in the bushes of a park. He is identified as 44-year-old Mauricio Nascimento, who was homeless at the time of his murder. According to the pathologist, it is the most vicious attack he has ever seen – Mauricio has been kicked and stamped to death.Detectives from the Met's murder investigation team must find his attacker. The murder took place in an area used by rough sleepers and not covered by CCTV, usually a vital tool in police investigations. The team must rely on forensic evidence and hope there are witnesses to the crime. However, questioning of the rough sleepers who use the park produces contradictory stories and rumours but no firm leads.Two days after the murder, detectives discover what they believe could be a breakthrough. An analysis of Mauricio's financial records reveals his bank card was used after he was murdered. Detectives identify the man who used the card and arrest him, believing he may have killed Mauricio to steal the card. However, under questioning, the man says he was a friend of Mauricio's and had nothing to do with the murder. As further evidence confirms the man's story, he is released, leaving detectives with few leads while an extremely violent killer remains free.In Hounslow, north west London, a woman goes to police saying she was raped in the early hours of that day. She tells them that after a night out drinking with friends, she became unwell outside the house she was staying in. A man offered to help her, but she blacked out. When she came to, she was inside his house, and he was raping her. With details provided by the woman, the police identify the man, and he is arrested. Under questioning, he denies raping her and claims it was she who forced herself on him. Police now have 24 hours to either find enough evidence to charge or release him.