Synopsis for
Shadow of the Thin Man (1941)

In the fourth Thin Man movie, Nick, Nora and Asta picked up their detective hats again to help clear a friend of murder charge.

Nick was feeling lucky one day and took Nora to the races, but what was waiting for him was not winning - it was murder.

A jockey was found shot dead in a shower stole, rumoured to be the result of not co-operating with Fred Macy and Link Stephens, racketeers known for fixing races and taking illegal bets. Later that day, Nick got a visit from old friends Major Sculley and Paul. Major Sculley was the deputy director of the racing committee and was investigating Macy and Stephens with Pauls help. Nick was invited to join the sleuthing, but he turned them down.

The same night, Paul sneaked into Stephens office to look for a black notebook that records all of the bets and names of people who worked for them. Whitey Barrow, a fellow journalist who was on Stephens payroll found him, knocked him unconscious; only to get himself killed. No one saw who shot Barrow, but the night watchman saw Rainbow Benny left immediately after the shooting.

Nick and Nora again found themselves in the wrong place at the wrong time. But seeing that Paul and his fiancée Molly (Stephens secretary) were accused of murder, they had to play detective to save Paul and Molly.

Nick quickly solved the first murder with Asta's help. The jockey's death was an accident, the gun fell and the accidental shot killing him. Nick persuaded Lieutenant Abrams to let him release false reports, claiming that the jockey and Barrow were killed by the same person; thus forcing the murderer to act. The trick worked and Nick was able to narrow the suspects down to three: Rainbow Benny, whom the night watchman saw leaving the office right after the shooting. Claire Porter, Stephen's British socialite girlfriend, who was really an ex-con. And Fred Macy, whose alibi was fa.

Nick went to Barrow's apartment to look for more clues and found both Claire Porter and her diamond bracelet. She confessed that Barrow was blackmailing her, threatening to expose her past to Stephens. She could no longer come up with the money he asked for, so she gave him the bracelet.

Having raised enough reasonable doubts, Nick was able to get Paul and Molly released. As he and Nora took the newly released lovers out to dinner, they ran into Rainbow Benny; but he slipped away when a fight broke out in the restaurant.

At Nick's request, Major Sculley used his influences and found out where Rainbow Benny lived. Wanting to use Benny as a co-operating witness for his case against Stephens, he joined Nick and Lieutenant Abrams as they rushed to Benny's apartment. They found Benny dead, strangled to death and then staged as suicide.

By now Nick had a pretty good idea who the murder might be, but could not be sure. So he had Lieutenant Abrams gather all suspects in the police station, hoping that one of them will be careless enough to make a mistake. And someone did.

It turned out that Rainbow Benny had been living in fear of his life and had just moved apartments the night he was killed. So whomever knew of his latest address, would be the murderer. With the door locked and a room full of police officers, Major Sculley was trapped.

Seeing that there was no escape, Major Sculley grabbed Nicks gun, wanting to take everyone down with him. Nora jumped on him to protect Nick and was overpowered by Major Sculley. This gave the police a break to get in, and after a rugby-style struggle, a relieved Lieutenant Abrams had the gun in his hands. He then found out that it wasn't even loaded!

Nick had been carrying empty guns for years, ever since Nicky Jr. was old enough to play with them............