La Guérison des Dalton
René Goscinny
 A famed psychologist announces that crime is a psychologically-based personal inefficiency which can be cured by therapy, and he chooses the Dalton Brothers as his test subjects. But the story experiences a major twist: not only does the experiment fail spectacularly, the doc also decides to participate in the Daltons' exploits! Once more it is up to Lucky Luke to remedy this delicate situation.