Lucky Luke arrives at Navajo City just in time to sign up for the town's big rodeo. But the prize money promised to the winner is attracting some unsavoury types, and among the participating cowboys is one Cactus Kid, an unrepentant bully and outlaw. The clash is inevitable, both in and outside the arena, and Luke will have to fight with his customary aplomb and humour - before riding off to new adventures.