Ariel's life is collapsing: her dad is dead, Mom lost her job, and now there's talk they'll have to move out of her beloved childhood home. With her senior year cross country season behind her and so much at stake, she and her twin sister, Sam, think of the only obvious solution: enter and win the legendary Leadville 100: an ultramarathon known for its low completion rate and high prize purse.

$500,000 to be exact.

With three state cross country titles, three National wins, and the support of her closest friends, Ariel has the relentless determination and audacity to believe she can hold her own against the professionals despite most people telling her she doesn't stand a chance. But when she loses the support of one of her best friends, Ariel begins to question everything. If she has a chance at winning, it's going to take more determination and grit than she's ever had to give.