Résumé: In 1874, President Grant authorises the construction of a bridge over the Mississippi. Until then, passage between St. Louis and East St. Louis was only possible on ferries. But the ferry company is owned by two brothers who have been getting rich by forcing passengers to wait in the hotels and restaurants they own on both sides of the river. The two crooks are doing everything in their power to prevent the bridge from being built - until Lucky Luke arrives, of course...