In Harper Lee's Chapter 15 of To Kill a Mockingbird, Scout demonstrates a great deal of bravery that serves to rescue both her father and Tom Robinson from a lynch mob.
Jem, Scout, and Dill witness a group led by Sheriff Heck Tate come to Atticus's door and start to talk with him. When he asserts he wants the truth to be known concerning what happened to Mayella Ewell, the three kids follow Atticus to the county jail. While outside of the county jail, a different mob approaches Atticus, this time led by Walter Cunningham. The mob tells Atticus to move away from the jail door he is guarding, insinuating that they are there to lynch Tom Robinson, not caring if he has a fair trial or not.
When Scout realizes her father is in danger, she very bravely comes out of hiding and runs toward him, followed by Jem and Dill. Fearing for their safety, Atticus orders the children home, but they refuse; Jem especially stands his ground. When a man from the mob grabs Jem's collar, saying, "I'll send him home," Scout kicks him in the sensitive area. When Scout recognizes Walter Cunningham among the men, she starts up a friendly conversation with him that clearly makes him feel ashamed; the other men feel shocked at her audacity. During the conversation, she especially asks him to say hello to his son Walter in her class for her and reminds Mr. Cunningham of Atticus's generosity in helping Mr. Cunningham with his entailment problem. More importantly, her conversation with Mr. Cunningham turns the tide of events. As soon as Scout shows her civility by conversing with Mr. Cunningham, reminding him of his civility too, he bends down, grips both her shoulders and says, "I'll tell [Walter] you said hey, little lady." He is then described as standing up, waving his "big paw," and saying to the rest of the mob, "Let's clear out ... Let's get going, boys," and as quickly as that, the mob breaks up and leaves.
Hence, Scout manages to rescue Tom Robinson from a lynch mob by bravely approaching the mob and conversing with Mr. Cunningham in a way that reminded him he was in reality a civilized person.
Scout playd a major part in stopping the lynching party by inserting herself in the situation. Her presence, and her innocent, but penetrating questions caused the men in the lynching party to see themselves through her eyes, and to moderate their actions for her sake. It caused them to reflect upon the many unintended consequences of their ill-considered actions by allowing them to see the impact those actions would have not just on Scout, but on their own children who would have to contend emotionally with what their fathers were about to do. Additionally, because of Scout's intervention, the men are reminded of their relationship to Atticus as a friend who had shown them compassion, who had selflessly helped them in their time of need, and who did not deserve to be put in jeopardy so that they could exact their own version of revenge. In short, she shamed them into backing down without one harsh word, without any accusation, without anything but a series of innocent, thoughtful questions that gave them back their humanity and their sense of right and wrong.