Society sleuths Nick and Nora Charles investigate a murder aboard a floating casino.　　Nick and Nora Charles are attending a charity benefit aboard a gambling ship.　　After a murder occurs, suspicion falls on Phil Brant, who had argued with the victim earlier in the evening.　　When Phil and his wife seek help from Nick and Nora, Nick refuses to get involved.　　But when shots are fired outside his own apartment, Nick begins to investigate, and he soon finds himself in a confusing case with numerous suspects.　　Nick and Nora Charles were the ultimate screen couple, husband and wife detectives, always in step and never missing an opportunity to outwit one another as they solved each crime, which they did just in time for the movie's ending.　　Myrna Loy was a fantastic Nora, the ideal wife and considering she made 14 movies with William Powell, she made it look like they were really married.　　The Thin Man movies, all six of them, played more like sophisticated screwball comedies than murder myst