Ne'er-do-well Tom Newcombe is publicly hanged for murdering a woman because the local school teacher, Celia Ames (Colleen Dewhurst), refuses to alibi him. A mysterious man, Paul Taylor (Hugh O'Brien), comes to town, signs on to work as a Shiloh Ranch hand and begins romancing Celia. However, his odd behaviour begins to raise the suspicions of Judge Garth and the local Sheriff who wonder about the motives of the stranger.

Three men, who are prison escapees, come to Shiloh looking for Judge Garth. One of those men (Barry Sullivan) turns out to be Betsy Garth's real father, a fact unknown to Betsy. The man aims to reclaim his daughter and receive compensation, believing the Judge abandoned him purposefully in the wasteland some years before.

Twin sisters Judith (Carol Lynley) and Susan (Shirley Knight) Morrow, who are the daughters of a deceased friend of Judge Garth, come to Medicine Bow where Susan is to start a pottery. Also arriving on the same train is a sailor, Kevin Doyle (Tom Tryon) who wants to settle down and become a farmer. While Susan is more reserved and practical, Judith dreams of seeing exotic places and is captivated by Kevin's stories of travel to faraway lands. They begin seeing each other but Judith seems to act strangely. Kevin finds himself so in love with Judith that he agrees to give up his dreams of settling down and take her to the places she has always wanted to see...but her problems are such that this will never come to be.

Judge Garth and Betsy are among the passengers on an overcrowded stage which is waylaid by an outlaw gang led by Pauk (Paul Richards). The passengers are trapped in a way station and the outlaws demand that one of the male passengers, a George Wilson who is traveling incognito, be given to them. Wilson is a former outlaw who had betrayed the gang. The various passengers must decide whether to live with their consciences and hand Wilson over, or risk their own lives in a gun battle with the desperate gang.