Nick Charles (William Powell) is taking his son Nick Jr (Dickie Hall) out for a walk in the park with their dog, Asta, but Nick Jr is growing bored so Nick Sr offers to read him a fairy tale out of his book. What he actually reads is the horse racing form, not knowing he is being spied on from his own apartment window by his wife Nora (Myrna Loy) and their maid Estrellita (Louise Beavers); Nora knows what will send him back home, and starts mixing cocktails. After a drink or two, the couple set out for the racetrack but Nora thinks Nick is driving too fast, which is proven when they get stopped by a policeman for speeding. He gives them a ticket, but is nevertheless happy to see them as Nick's renown with the law knows no bounds, and escorts them to their destination - very slowly. On the way they are overtaken by a host of police motorbikes and an ambulance... could there be trouble at the track?
Shadow of the Thin Man was the fourth in the popular Thin Man series, with Powell and Loy returning along with director W.S. Van Dyke; sadly this was to be his last entry in the series as he would commit suicide before the next was made. There were new writers on board, Harry Kurnitz, who also wrote the story, and Irving Brecher, and this is the first of the films not to be based on a Dashiell Hammett plot, but the formula is well established by this point, with Nick reluctantly drawn into a murder conspiracy and a few stops along the way for comic interludes. Nora makes more of an effort to be involved with the detecting this time, even succeeding in uncovering the odd item of crucial evidence, and for historical value there's the novelty of seeing legendary acting teacher Stella Adler playing one of the suspects in a supporting role (she gets a couple of good lines, too).
When Nick and Nora turn up at the racetrack they meet a commotion because a jockey has been found shot dead, and the police are there to investigate a murder. A running joke of the series, particularly overdone by this episode, sees Nick recognised wherever he goes, if not by the cops then by the more shady types, so obviously when they all see him there they immediately assume that he will be taking charge of the case. And he does in his way, uncovering a gambling plot, but deducing that the jockey was not murdered - he accidentally killed himself. Someone who didn't kill themselves is found shot dead however, and it's up to Nick to clear the name of newspaperman Paul (Barry Nelson) who is prime suspect. Adding interest this time around the almost inevitable rising star is Donna Reed, playing Paul's fretting girlfriend, and there is possibly the first sighting of the old "Follow that car!" - taxi zooms off without them - gag. All this and Tor Johnson with hair, too! Not a bad entry, then, as everyone has long ago settled into this series nicely. Music by David Snell. Why do they keep slowing down and speeding up footage of Asta in this one, though?