Superintendent Grodman of Scotland Yard built an airtight case into a noose around a killer's neck. Then, too late, evidence exonerates the hanged man. Grodman retires in shame. Then a new case, a diabolical locked-room murder, gives Grodman the chance to redeem himself. Sydney Greenstreet and Peter Lorre play Grodman and his effete artist comrade, hunting for clues in the fog-bound, gaslit streets of 1890 London.