After killing a prison guard, convict Robert Stroud faces life imprisonment in solitary confinement. Driven nearly mad by loneliness and despair, Stroud's life gains new meaning when he happens upon a helpless baby sparrow in the exercise yard and nurses it back to health. Despite having only a third grade education, Stroud goes on to become a renowned ornithologist and achieves a greater sense of freedom and purpose behind bars than most people find in the outside world.

Running from the law after a bank robbery in Mexico, Dad Longworth finds an opportunity to take the stolen gold and leave his partner Rio to be captured. Years later, Rio escapes from the prison where he has been since, and hunts down Dad for revenge. Dad is now a respectable sheriff in California, and has been living in fear of Rio's return.