Four friends embark on a trip with 16 wild Mustangs, a journey that will change their lives. For five adventurous months, the friends ride through the American West. Their route takes them through the majestic Grand Canyon, Yellowstone, and Glacier National Parks. For their trip, the young men select 16 Mustangs which they adopt from the US Bureau of Land Management. The animals are perfectly adapted to the rocky landscape, the severe desert climate, and the mountain trails and are to accompany the friends through unspoiled landscapes, from Mexico to Canada, over 5000 kilometers. Due to overpopulation, some 50,000 Mustangs and donkeys are kept and managed on state-run facilities in the USA.

Although the route has been planned with great care and well in advance, the four friends and their companions must constantly adjust and surmount ever-changing uncertainties like snow, downpours and prairie fires. They ride through merciless heat, cross raging rivers and steep chasms and encounter jumping cacti, rattlesnakes and aggressive elk. But also sickness, injuries and fatal accidents befall the group on their journey. Even though not much of the idealized romanticism of the American wild is felt in reality – a deep friendship develops between the men in the stunning natural landscape, and an incomparable bond between man and Mustang.