It's been ten years since world-famous explorer Professor Peterson went missing. When his granddaughters and their new friends discover his ancient journal, they stumble into an unexpected world of adventure. Each new clue they discover could bring them closer to solving the mystery surrounding their grandfather's strange disappearance, if only they could open his journal to understand them. But someone else wants the journal and its secrets for themselves. Will the children be able to find the answers in the journal before it falls into the wrong hands?