Archaeologist Dr. Michael Stone looked for the lost medallion his entire life, and now his son Billy has taken up the search. Amazingly, the medallion ends up in Billy's hands and a spontaneous wish in a precarious situation takes Billy and his best friend Allie, back 200 years to what they realise is a very different Aumakua Island. When Billy and his friends are not jumping off waterfalls, avoiding animal traps, crossing the ocean, sneaking through caves or escaping a prison they're facing their nemesis Cobra, who wants nothing more than for them all to disappear. With no other way to get home, and the wellbeing of the entire island resting on his shoulders, Billy must discover the key to reclaiming the medallion and its tremendous power. One way or another, this adventure will change Billy, and life on the island, forever.