When the body of a young woman is discovered deep beneath the icy waters of Lake Grant, a note left under a rock by the shore points to suicide. But within minutes, it becomes clear that this is no suicide. It's a cold blooded murder. All too soon former Grant County medical examiner Sara Linton - home for Thanksgiving after a long absence - finds herself unwittingly drawn into the case. The chief suspect is desperate to see her but when she arrives at the local police station she is met with a horrifying sight - he lies dead in his cell, the words 'Not me' scrawled across the walls...