Jon Klassen's debut picturebook. This is an unforgettable whodunnit with a cast of forest creatures. A sensitive bear has lost his hat, and interviews the characters nearby to see if he can find it. The readers will certainly guess the culprit before the bear, making this a very playful reading experience. Paperback. This is the first book in a trilogy, which also includes This Is Not My Hat and We Found A Hat.  Read our blog about why adults and children both love Jon Klassen, and how he got into picture book making, here! Format: Paperback