Dion Leonard, a seasoned ultramarathon runner, crossed paths with a stray dog while competing in a 155-mile race through the Gobi Desert in China. The lovable pup, who would later earn the name Gobi, proved that what she lacked in size, she more than made up for in heart, as she went step for step with Dion over the Tian Shan Mountains, across massive sand dunes, through yurt villages and the black sands of the Gobi Desert, keeping pace with him for 77 miles. As Dion witnessed the incredible determination and heart of this small animal, he found his own heart undergoing a change as well. Whereas in the past these races were all about winning and being the best, his goal now was to make sure he and Gobi's friendship continued well after the finish line. He found himself letting Gobi sleep in his tent at night, giving her food and water out of his own limited supply, and carrying her across numerous rivers, even when he knew it would mean putting him behind in the race, or worse, prevent him from finishing ...