The Thin Man Goes Home

Nick and Nora visit Nick's parents in Sycamore Springs, where the locals treat Nick as though he's here on an official investigation. Nick denies being there to investigate, trying to keep things normal. The town's suspicion provides a tense backdrop for the unfolding events.

Peter Berton, an aircraft factory employee, seeks out Nick but is shot dead before he can reveal anything. The murder signals a larger conspiracy and pulls Nick deeper into the case. The mystery tightens as key information vanishes with him.

Dr. Bruce Clayworth performs the autopsy on Berton's body and extracts a pistol bullet. The recovered bullet hints at a more sophisticated weapon and a planned killing. This discovery steers Nick toward a spy-driven motive behind Berton's death.

While Nick searches Berton's room for clues, he is knocked unconscious by Crazy Mary, the town's eccentric. Nora is left to piece together what happened from the sidelines. The disruption heightens the stakes and narrows the investigative path.

Nora innocently purchases a painting as Nick's birthday gift. Seeing the painting brings back unpleasant memories for him, prompting her to donate it to a charity bazaar. The artwork's significance to the case begins to surface, linking art to espionage.

Edgar Draque offers Nora a large sum for the painting, arousing Nick's suspicion about its true value. The offer hints at motives beyond mere art collection and points to hidden interests. The painting becomes a coveted item for more than decorative purposes.

Nick learns that Draque's wife Helena bought the artwork, but she is knocked out and the painting disappears. The theft deepens the mystery and suggests deliberate subterfuge by those involved in espionage. The missing painting becomes a critical clue.

Nick discovers Crazy Mary is Berton's mother and goes to see her, only to find her lifeless body. The revelation ties the players together in a disturbing way and intensifies the danger surrounding the case. The investigation now has personal stakes for several townspeople.

Nick's dog Asta locates the painting hidden in Crazy Mary's shack, reuniting the artifact with the mystery. This discovery strengthens the link between the painting and the espionage plot. It also suggests Mary’s place is connected to the hidden blueprints.

Nick arranges to bring all suspects to his father, Dr. Bertram Charles, and uses his influence to facilitate the confrontation. The family setting becomes a strategic stage for pressuring confessions and exposing the spy network. The scene marks a turning point in the investigation.

Using Dr. Charles's fluoroscope, Nick reveals a blueprint hidden beneath the painting's surface. The diagram is part of the specifications for a new aircraft propeller coveted by a foreign power. The reveal ties the case directly to national security concerns.

Berton had copied the blueprints and planned to confess, but was killed by the spies before he could reveal everything. Nick also brings in a World War II Japanese Nambu sniper rifle—belonging to Dr. Clayworth's brother—as a potential murder weapon, underscoring the reach of the conspiracy. The pieces suggest a coordinated cover-up.

Nick identifies Dr. Bruce Clayworth as the leader of the spy ring, using Berton's bullet as a pivotal clue. Clayworth grabs the Nambu rifle and confesses to the murder, revealing a long-standing hatred for Nick. Nick had removed the firing pin from the rifle, preventing a fatal shot, and his father is left deeply impressed by the resolution.