A killer is using labyrinthine storm drains to dispose of his victims, who are found handcuffed and drowned, washed out of the rain-filled drainage lines like garbage. The crimes compel FBI Agent Tess McCallum to crack the case, but they're touching a nerve in Personal Security Consultant Abby Sinclair. She fears it's the same madman who invaded her nightmares once before. As the two women work with each other to solve the case, tensions rise and tempers flare. And as sure as the rain, a new killing season begins.