Pepe Le Moko (Tony Martin) mène une bande de voleurs de bijoux dans la Casbah d'Alger, où il a lui-même exilé à échapper à l'emprisonnement dans sa France natale.
Maria San Carlos, the only daughter of a wealthy landowner, is betrothed to Escobar, a General in the Mexican Revolution, but she does not love him. Escobar sends a mixed gang of Americans and Mexicans to capture her and bring her to him. Complications ensue when an American cowboy, who had been hitching a ride with Maria's entourage and has his gold stolen by the gang, pursues them across the desert.