California,1958. In the coastal sprawl between orange groves and neon strip joints, Frankie “Grease” Martino makes a living turning battered coupes into chrome-bright hot rods and hunting rare 45s after hours. Then a client’s Cadillac arrives for a routine carburetor tune-up, and Frankie finds a bloodstained leather jacket stuffed in the trunk. Before he can decide whether to call the cops or keep his head down, Johnny Vale—the swaggering lead singer of local rock & roll darlings The Thunderbolts—is found drowned in a marina slip. Everyone says it was a drunken accident. Frankie hears a different rhythm. With sock hops, body shops, jealous lovers, payola schemes, and a whole town humming with gossip, Frankie has to solve a murder before the killer decides the nosy mechanic should be the next thing to disappear beneath the tide.