An encounter with Thor, the god of thunder, turns 16-year-old Adrian Blackwell's life on its head. Just a few months ago, Adrian has lost his father in a car crash. But was it an accident? Shortly before his death, the expert in Old Norse mythology is said to have unearthed a magic rune incantation that can allegedly be used to open a portal to the realm of the dead. It is there that the enemies of the Asgard gods have taken the gods' life-prolonging apples, without which the last of the gods are doomed. At least that's what Thor claims when he asks Adrian to retrieve the lost incantation, but Thor isn't the only one who wants it. Fenrir, the wolf who longs for the downfall of the Asgard gods, is also after the incantation. He threatens to kill Adrian and his mother if he doesn't deliver it to him by sunset, but Adrian doesn't even know where to begin looking. Adrian is forced to decide whether to save his mother's life and his own, or to save the ancient Asgard gods from destruction. His journey is helped by two girls who could hardly be more different but complicated by the fact that he can't figure out which of the two he has fallen for. His quest takes him to London and then to the realm of the dead. There, he is reunited with his deceased father, but he also meets Hel, the sinister ruler of the realm of shadows. There is only one way back to life: Adrian must face his greatest fear.