Somewhere in London, a lonely young woman is reaching out to the wrong man. It's up to Detective Inspector Mark Tartaglia and the rest of the Murder Squad to find her before a killer does. When fourteen-year-old Gemma Kramer's broken body is found on the floor of St. Sebastian's Church, the official ruling is that she jumped to her death from the organ gallery above the altar. But then a witness comes forward claiming to have seen Gemma kissing a much older man before the two disappeared into the church together. And when the toxicology report reveals traces of GHB and alcohol in her system, a full-scale murder investigation is launched. At the helm is Detective Inspector Mark Tartaglia, a stubborn cop known for following his hunches. It's Tartaglia's first time in charge, and he walks right into a political minefield as the investigation turns up three more suspicious deaths—all involving vulnerable young women falling to their deaths, all initially ruled suicides. In the whirlwind of conflicting theories from the media, criminal profilers, and cautious administrators, Tartaglia and his detectives must connect the dots between victims to find a serial killer with a chilling predilection for lonely girls and deadly heights.