When librarian Valerie Tremt gives student Luis Ramirez a chance to go back in time, he knows just what he wants to do. He plans to go back to 1696 and see exactly where Captain William Kidd left buried treasure, and then return to the spot and retrieve it. He'll be rich and famous But when he returns from his time traveling adventure without any treasure, he is inconsolable. To make matters worse, his older brother Rafael doesn't believe he time traveled at all. Luis decides there's only one way to convince him. He brings The Book of Memories home to show Rafael, despite Ms. Tremt's warning that the book is never to leave the library without her permission. Luis ignores her warning--after all, it's just a book. What could possibly go wrong?

Turns out--a lot. When Luis wakes up to find a Viking, Charlie Chaplin, and King Tut wandering around his house, he realizes Ms. Tremt's warning was no joke. The good news is now Rafael believes him. The bad news is that it's not going to be easy to get these historical figures back to their proper time periods, especially because none of them want to go home Can Luis find a way to put everything--and everyone--in the right place before time runs out?