Billy Johnson, the son of two world-famous explorers (who mysteriously disappeared eight years ago) has big dreams. The teenager may be a part-time janitor now, but exploring is in his blood. He just needs one big discovery to prove to the Explorers League that he's worthy of the rank of Ace Explorer. Luckily, Billy has an ally in his best friend, Barrace. Not only is Barrace a college professor of linguistics, but he's also a duck! Together, these boon companions brave hidden jungle kingdoms, haunted tombs, deadly deserts, and treacherous mythological trials to uncover the mysteries of the world. But will they discover that the biggest mystery of all may be following them every step of the way?