Marcus Mender can fix anything just by holding it. But now, he can't stop! Like King Midas and the golden touch, everything becomes new and perfect in Marcus' hands. Before he can control his new power, the Troubled Tweens are sent to South America on a magical mission: to recover a rare magnetized lodestone before the Loki, the magic thieves, use it for their own selfish purpose. But the lodestone's magnetic field causes a reversal between positive and negative, turning the Loki into heroes and the Troubled Tweens into villains out to steal more power. Only Marcus' ability to fix the lodestone can save them, but with the switch of good and evil, Marcus will have to struggle to make the right choice.