Sam the library mouse and his friend Sarah are off on a new adventure. This time they leave the library behind and go to a museum so Sam can make sketches in his explorer's journal. Sarah isn't so sure that explorers have the time or the interest to write in journals. But Sam shows her that a journal can contain anything, from a ticket stub to drawings of cool things like dinosaurs and ancient Egyptian mummies. As they explore the museum, they see all kinds of art and unexpectedly make friends with another artist. The latest book in this bestselling series is sure to entice readers to come along on the museum adventure.