Leandro and Odon want to join Alvaro Obregon's revolutionary forces. To do so, they travel to the north of the country on a zebra that they found in a broken down circus, believing that it is a gringo horse. They have several adventures during their journey: they escape from women who enslave them, they meet General Quesada, who wants to found a New Republic, they get lost in the desert, etc. When they reach Obregon's army, a colonel thinks they are Villa's spies and puts Leandro and Odon to a hard test of loyalty.