In English comedy at its blackest (and funniest) pitch, this droll 1955 farce finds Alec Guinness in one of his typically deft, chameleon turns as would-be criminal mastermind Professor Marcus. When Marcus's grand plan to pull off a train heist leads him to a strategically situated house occupied by the genteel Mrs. Wilberforce (Katie Johnson), the ensuing masquerade triggers a mordant, even macabre comedy of manners. With Marcus and his rough-hewn cronies (Herbert Lom, Peter Sellers, and Danny Green) posing as a string quartet, and the dear lady's demise seen as the means to their larcenous end, the gang's sinister machinations are consistently, if unwittingly, foiled by the good-hearted, resourceful widow. --Sam Sutherland