Hardscrabble street kid Lorraine Kowalski yearns to escape her dead-end life in Southwest Philadelphia. Wealthy Main Line debutante Daven Barrett just as strongly desires to break free of the shackles imposed upon her by her privileged upbringing. Their chance encounter during the summer of 1983 reveals an uncanny physical resemblance, which emboldens them to hatch a daring plan: to switch identities for the summer.

Lorraine navigates the schemes and machinations of Philadelphia high society, while Daven learns the art of survival on the city’s mean streets. Each girl discovers that the world into which she has intruded is as fraught with danger as the world she hails from. But when the summer ends, and they resume their true identities, will they part as friends? Or will they walk away from each other for good?