The body of a young girl lying face down in a swimming pool—white tennis shoes still on her feet, chestnut hair fanned out like a halo—is the last thing Detective Josie Quinn expects to find on an early morning visit to see her brother before class at Denton University. But when she recognizes the girl’s face as she drags her limp body from the water, there’s only one question racing through Josie’s mind: how does a champion swimmer accidentally drown?Nysa Somers’ family are distraught. She was a model student, beloved daughter and everybody’s friend. There’s no way she would do anything reckless enough to put her scholarship at risk, let alone her life. It’s up to Josie and her team to piece together what happened in the hours leading up to Nysa’s death, and that begins with finding her missing backpack.But the bag, discarded in the woods on the nearby campus, contains nothing more than empty food wrappers, Nysa’s phone and a cryptic calendar entry telling her to be a mermaid.The next day, a terrible housefire envelops the nearby home of a retired fireman, nearly killing his two granddaughters. The last words the little girls heard him mutter before he set the blaze were, be a match.As the body count rises, it’s only Josie who can see the deadly pattern forming. Can she convince her team that the wrapper found in Nysa’s bag is the crucial link they’re missing? Josie knows she must go it alone if she’s going to stop this silent and calculated serial killer before any more precious lives are taken.But with the killer finally in her sights, Josie takes a dangerous risk and finds herself hanging onto life by her fingernails. Can she trust her team to save her, and before it’s too late?