There is a town in Ireland where people still do Halloween the old-fashioned way: an annual sporting competition to honor the Spirits.

Every year, the perfect, prestigious O'Dell family makes an absolute mockery of the lovable but laughable Flanagan family at The Spirit Games, dashing their dreams of winning. But this year, teenage troublemaker Pad Flanagan plans to change everything: he tricks the Spirit of an ancient Celtic hero into training his family for the big event...accidentally opening a supernatural floodgate of mischief, magic and monsters that threatens to destroy his town.