帕勃原是流浪部落的首长，在妻子因生老幺（小儿子）阿席亚死于难产后，即因悲伤自责而带著儿子远离部落，搬到都伯林定居。有一天，阿席亚和提多的外祖父华德从外地旅游归来，带回一匹神骏的白马，怎之惹来马贩诺尔的觊觎，并夥同狡诈的警长以非法的手段将白马占为己有。追捕的脚步亦步亦趋，手无寸铁的孩子当如何对抗恶势力的压迫？帕勃又该如何才能顺利救出孩子脱离险境？A gigantic white stallion appears mysteriously to a Traveller grandfather and his two grandsons in an Irish slum. Since, puzzlingly, the younger of the two boys is the only individual who can control the horse, ownership falls to him and his older brother by default. There being no place for the animal, they move him into the apartment of their alcoholic Traveller father. Police remove him and, in a shady deal, he ends up under control of a wealthy, underhanded horse breeder. The boys manage to retrieve him and escape on his back, but the stallion seems to have his own travelling agenda.
