One day Shari Grantner, a tall red-haired lawyer, is running a successful open water swim clinic. Less than 24 hours later, her body washes up on a beach near San Francisco. Shari's sister reaches out to Trisha Carson, an amateur sleuth, asking for her help. Trisha jumps into the investigation and soon discovers that the seemingly strait-laced barrister had a sizzling secret life. As Trisha inches closer to the culprit, the trail circles back to a familiar location where the killer is waiting.