Polar bears have a reputation for trouble, and Irving and Muktuk carry on the tradition in their benign, zoo-bound way. This third installment finds the bears busy poking fun at a white bunny (having first confused it with a small polar bear): “Grass-eater! Grass-eater!” they chide. The bunny takes offense and remedial action, kicking Irving in the ankle and nipping Mukluk’s toe. The bears flee and cower, though they put up a brave front later when invited to a party outside the zoo: “You know, we are not to be trusted.” The bunny is also a guest; the bad bears cringe and behave like altar boys. Perhaps Daniel Pinkwater has beveled the bears’ naughtiness too much, knocking them from their perch as congenital miscreants. However, this new twist—bullies who’ve been cowed—is yet another black mark for the boys, one they will likely wear with clueless pride. And Jill Pinkwater has made sure that the bears, on that last page, still sport the glint of subversion in their eyes—albeit under pink party hats. (Picture book. 4-8)