Tristan can't easily deflect the world's commentary on his weight, but his quick wit keeps him from being engulfed by self-consciousness. Unfortunately, by tenth grade, he finds making his way in the world as a heavy kid more complicated by the arrival of Kelly, the beautiful, popular, and nutrition-obsessed daughter of his mom's new partner. When Kelly takes up with Tristan's exploitive friend, Marco, Tristan's journey becomes an unpredictable ride on a pair of cross-country skis.