After being reformed for five years in the Wyoming pen, the celebrated criminal Mugs Birdsong decides to found a crime academy that will instruct lawmen on the ways of means of lawlessness. He sets up shop in an abandoned orphanage in Rock Springs, and soon is instructing classes in bank robbery, train robbery, and various other sterling occupations. He sells autographed wanted posters, and persuades a banker to let him stage a mock robbery at the bank, for the benefit of his students—and that's when the fun begins.