Stupid Young Heart is a story about the first love of lightly built, carefree Lenni and gorgeous and popular Kiira. Not yet even properly in a relationship, they discover that they are expecting a baby, and decide to keep it – partly as a statement to their families who have lost touch with what goes on in the teenagers’ lives. Lenni then has nine months to become a man. Having grown up without a father figure, Lenni receives some yearned for adult attention from an unlikely friend JANNE (40), a member of a right wing activist group. After taking part in a scrambled attack on a local Mosque, while Kiira is rushed to the hospital to give birth, Lenni realises that he can be a man in his own way, even if he never had a chance to be a child himself.