Mouk and Chavapa are in Argentina, where they meet Chaco. Chaco is a cowboy, or a "gaucho", as they're called in Argentina. His job is to gather up his herd and take his cows back to his ranch. Mouk and Chavapa offer him to give him a hand, but they will soon find out that herding cows isn’t as easy as they think.
Mouk and Chavapa travel by bus in the outback with Sidney, his father and two other passengers: Nina and her grand-mother. Unfortunately, the bus breaks down and there no water left in the radiator. Luckily, they find a watermill and try to repair it.
