A family witnesses two murders by a gang leader and is intimidated not to testify against him, except for the grandfather.
The Leeds family gathers for dinner. Pa Leeds (Grant Mitchell) argues with his son Jackie Leeds (Edward J. Nugent) about finding a job and the value of his work as an accountant. Grandpa Summerill (Chic Sale) arrives from the soldiers' home for a two-day visit. Men from two cars shoot in the street; Maxie Campo (Ralph Ince) knocks down Grandpa and goes out the back. A cop and the informer were murdered. District Attorney Whitlock (Walter Huston) tells the Leeds family how Maxie Campo and his men killed the informer. Everyone in the family identifies the photo of Campo, and Whitlock orders his arrest.
Horan shows Mr. Leeds a police badge but takes him in a car to the gang. Big Jack (Nat Pendleton) tells Mr. Leeds it wasn't Maxie Campo and offers him a vacation or $5,000. When Pa Leeds say no, Big Jack beats him up. Ma Leeds (Frances Starr) worries, because Pa is late. Jackie Leeds overhears Whitlock tell his deputy Thorpe (Russell Hopton) that Campo's gang might kill the whole family; but Whitlock assures Jackie he will protect them. Ma cares for the injured Pa, while the house is guarded by police. Grandpa lectures Jackie about duty, and police escort Sue Leeds (Sally Blane) to the store. The two kids miss school. Whitlock comes in to take testimony. Ma discovers that Donny Leeds (George Ernest) went to play baseball. Big Jack calls to warn them not to testify if they want to see Donny again. Pa and Ma refuse to testify. Whitlock threatens Ma and Jackie with jail. Grandpa says he will tell the truth, and the civil war veteran gives a patriotic speech why it is important. Sue says that Grandpa was drunk; but he tells Whitlock he was not. The police search Campo's area for Donny. Whitlock tells Thorpe that he won't bargain with gangsters, and he learns that Grandpa, his star witness, has disappeared. Grandpa is looking for Donny.
Jackie Leeds testifies that he can't identify Campo. The police search the building where Donny is held but don't find him. Sue testifies that Campo looks like the man. Grandpa plays his flute in the street. Donny hears the flute and throws his baseball through the window. The police grab Grandpa Summerill; but he runs off and shoots at the gang. Just when the judge is going to dismiss the case, Whitlock gets a call from the police. Grandpa and Donny come in to testify. After Campo is executed, Grandpa visits the veterans' cemetery.
This story explores the conflict between a family's threatened security and the larger public good of stopping violent criminals. The aged veteran risks his life and is even willing to sacrifice his family's safety, because he believes that gangsters should not be allowed to control things.