Abraham Cahan, editor of the Jewish Daily Forward, serves as the conscience of the Jewish ghetto teeming with rogue cops and swindlers.

He rescues Ben Ravage, an orphan, from a trade school and sends him off to Harvard to earn a law degree. But upon his return, Ben rejects the chance to escape his gritty origins and instead becomes a detective for the Kehilla, a quixotic gang backed by wealthy uptown patrons to help the police rid the Lower East Side of criminals.

Charged with rooting out the Jewish 'Mr. Hyde', a half-mad villain who attacks the prostitutes of Allen Street, Ben discovers that his fate is irrevocably tied to that of this violent, sinister man.