Come Fill the Cup gets a bit too melodramatic for its own good, and it has other faults, but all its flaws are forgiven for one reason: it provides James Cagney with a showcase for an unforgettable tour de force performance. Cagney, one of the screen's most interesting talents, is usually a powerhouse in any role; here, he is given the chance to really let go, and the result is staggering. Playing an alcoholic is tempting to any actor; it's also fraught with danger, as it's easy to fall into caricature. Cagney doesn't slip for one minute, even when his character is as miserable an alcoholic as it's possible to be. His walk, his speech, his manner are all perfectly tuned. And when he becomes a recovering alcoholic, Cagney's work is equally impressive: the audience feels the burning desire that he continues to experience and equally feels is ironclad determination to resist that desire. It's a commanding performance through and through. But Cup doesn't rest or fall totally on Cagney. Gig Young turns in a truly fine performance, impressively scoring even as Cagney dominates, and James Gleason is also aces throughout. The screenplay is nowhere as good as the players, leaning on excessive melodrama and some incredible plot points; but it does provide an amazing sequence, in which Sheldon Leonard forces liquor into Cagney's throat, that is simply riveting.