A fugitive visits his sister's family, and her oldest daughter gradually learns that he is a murderer of widows.
Two men who came to see Uncle Charlie (Joseph Cotton) follow him. He sends a telegram he is going to visit his sister Emma Newton in Santa Rosa. Her daughter Young Charlie (Teresa Wright) wants Uncle Charlie to visit and learns he is coming. Joseph Newton (Henry Travers) and his family welcome him. Uncle Charlie hands out gifts to each. Young Charlie says she does not want anything except to know a secret about him; he gives her an emerald ring, and she finds a past inscription. Joseph's brother-in-law Herbie (Hume Cronyn) reads mysteries, and Joseph says how he would kill him. Uncle Charlie removes pages from the newspaper. Young Charlie finds them, and he grabs them back. Emma Newton (Patricia Collinge) tells Uncle Charlie that two men want to interview the family, but he rejects this. Uncle Charlie goes to the bank, embarrasses Joseph and casually gives the president a $40,000 deposit in cash. Jack Graham (Macdonald Carey) and Fred Saunders (Wallace Ford) come to the house and ask questions of Emma and Young Charlie, who lets them in her room because her uncle is not there. When Uncle Charlie returns, he demands the film from the camera. Young Charlie goes out with Graham, and she learns he is a detective who suspects her uncle. Young Charlie takes the news clippings and rushes to the library, where she reads about the "Merry Widow murderer."
Young Charlie tells her uncle that she had nightmares about him running away. He talks of rich widows with contempt. Joseph and Herbie talk of murdering, and Young Charlie gets upset and leaves. Uncle Charlie goes with her and takes her into a bar. She asks how he could do such things and puts the ring on the table. He says he is tired of running and asks her for one more chance. After church Saunders tells Young Charlie the photo proved her uncle is the wanted man; she says she will tell them when he leaves. They learn that the suspected murderer died. Graham tells Young Charlie that he loves her and says goodbye. She falls on a broken stair and suspects her uncle, who says he is not leaving. She tells him to go away, or she will kill him. She finds the motor running in the garage and is closed in. Herbie says someone is caught in the garage. They open it, and Uncle Charlie puts the key back in the car to turn it off. Young Charlie recovers and says she could not find the key. She tries to call Graham and finds the ring while the others are at Uncle Charlie's lecture. Uncle Charlie sees the ring and says he is leaving. He boards the train with Young Charlie and warns her that Emma could not stand the shock. As the train moves, the two Charlies struggle in an open door; Uncle Charlie is pushed out and is killed by another train. At the funeral Graham consoles Young Charlie.
Alfred Hitchcock directed this suspenseful drama about
an "average family" in a small town, making the vicious
uncle seem more horrifying.