When a huge fire breaks out at an American oil company in an isolated region of South America, boss Bill O’Brien (William Tubbs) decides that the best solution is to blow it out like a candle, using a nitroglycerin-induced explosion to do so. The nitroglycerin will need to be transported to the site of the fire by truck over rough roads, and O’Brien knows that no union will ever allow its members to take on such a dangerous job. He decides, instead, to hire some of the unemployed and underemployed foreigners living in the squalid nearby village, men longing to get away but too poor to afford it. Four of them end up driving the two trucks: Mario (Yves Montand) and Jo (Charles Vanel) in one, Luigi (Folco Lulli) and Bimba (Peter van Eyck) in the other. It’s a journey of some three hundred miles, and not a single inch is free from peril.