This last entry in MGM's "Thin Man" series isn't the best of the batch, but is a lot better than most other comedy-mysteries of the period. Older but no less glamorous and sophisticated, Nick and Nora Charles (William Powell and Myrna Loy) try to solve a murder on a gambling ship, thereby plunging into the rarefied world of Manhattan jazz nightclubs. Since this is alien territory for Nick and Nora, they must rely upon hep-talking clarinetist Clinker Krause (Keenan Wynn) to act as their guide. As the case progresses, several subplots converge, chief among them the furtive romance between socialite Janet Thayar (Jayne Meadows) and gambler Phil Brant (Bruce Cowling). When the Charleses get too close to the solution, it spells trouble for their 11-year-old son Nick Jr. (Dean Stockwell). The film's biggest surprise is that is that the actor who usually plays the "hidden killer" in films of this nature isn't the culprit this time around. In addition to its many other virtues, Song of the Thin Man offers one of the few credited screen appearances by "queen of the extras" Bess Flowers, here playing the wife of suspect Ralph Morgan.