In ancient India, tragedy strikes a young elephant trainer. Forced into a slave caravan that takes him through perilous lands and into a world at war, Ashoka befriends a special elephant. He and that elephant, Four Nails, together lead Hannibal's army over the Alps and down the back of Rome. Though a time of constant danger and uncertainty, Ashoka finds beauty and kindness while helping others enslaved for the pleasure of ruthless rulers. To survive this remarkable journey, the elephant trainer calls upon his unique ways with the great greys and a strength known only to those with nothing left to lose.