Michael Dahl 
Tome Raider [PDF ebook] 

A shadowy thief is haunting the Library of Doom. The crook is outsmarting all the Library’s ancient security devices, one by one. Nothing can stop him. But how is that possible? And what’s worse, the thief is heading toward the Library’s most amazing weapon . . . the Eye of the I, a gleaming pearl that can transform its owner into anyone else in the world! Can the Librarians stop the crook before it’s too late? This gripping mystery is followed up with discussion questions, writing prompts, and a glossary.