George and his large, simple-minded friend Lennie are drifters, following wherever work leads them. Arriving in California's Salinas Valley, they get work on a ranch. If they can just stay out of trouble, George promises Lennie, then one day they might be able to get some land of their own and settle down some place. But kind-hearted, childlike Lennie is a victim of his own strength. Seen by others as a threat, he finds it impossible to control his emotions. And one day not even George will be able to save him from trouble.