It is the week before Christmas when young and adventurous Pietari uncovers the truth about Santa Claus. Legend has it that the jolly old man is more of a foe than a friend. A group of American scientists is also looking to uncover some facts in Pietari’s quiet rural town in northern Finland. It turns out that the most well-kept Christmas secret ever lies 500 meters below ground. They’ll unleash an unforeseen chain of events, after which Christmas will never ever be the same again.