Hayley Mills plays twins who, unknown to their divorced parents, meet at a summer camp. Products of single parent households, they switch places (surprise!) so as to meet the parent they never knew, and then contrive to reunite them.

Hud Bannon is a ruthless young man who tarnishes everything and everyone he touches. Hud represents the perfect embodiment of alienated youth, out for kicks with no regard for the consequences. There is bitter conflict between the callous Hud and his stern and highly principled father, Homer. Hud's nephew Lon admires Hud's cheating ways, though he soon becomes aware of Hud's reckless amorality to bear him anymore. In the world of the takers and the taken, Hud is a winner. He's a cheat, but, he explains "I always say the law was meant to be interpreted in a lenient manner."

In 1912, the notorious and violent prisoner Robert Franklin Stroud is transferred to the Leavenworth Prison convicted for murdering a man. When a guard cancels the visit of his mother, Elizabeth Stroud, due to a violation of the internal rules, he stabs and kills the guard and goes to trial three times. He is sentenced to be executed by the gallows, but his mother appeals to President Woodrow Wilson who commutes his sentence to life imprisonment. However, the warden, Harvey Shoemaker, decides to keep Stroud in solitary for the rest of his life. One day, Stroud finds a sparrow that has fallen from the nest in the yard and he raises the bird until it is strong enough to fly. Stroud finds a motivation for his life raising and caring for birds and becomes an expert in birds. He marries Stella Johnson and together they run a business, providing medicine developed by Stroud. But a few years after, Stroud is transferred to Alcatraz and has to leave his birds behind.