Andrew and Kristine, two teenage orphans, find a mysterious crystal locket that is the key to time travel. As they are thrust deep into the past, Copycat, an aptly named know-it-all cat, becomes their unusual guide, along with Chaz, their dog. Andrew and Kristine are amazed to find themselves active participants in famous historical events that they had only learned about in school. On their journey, they will learn disturbing secrets, upon which the world's very survival rests. Shocking revelations about their family will also lead them to wonder just who they can trust...if they can trust anyone at all.
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