His Dark Materials
Lyra is a orphan who resides in a parallel world where science, theology and magic are entwined. Lyra's search for a friend finds a sinister plot involving kiddies that are stolen, also can become a quest to understand a mysterious phenomenon called Dust. She's later joined on her travel by Will, a boy who possesses a knife that could cut on windows between worlds. As Lyra learns the facts about her parents and her fate that was prophesied, both young people are caught up in a war contrary to celestial powers that ranges across worlds.