When Tumblebee meets a sad little monster, can he find a way to make him happy? Tumblebee is so excited to travel to his favorite daydreaming spot in Wetmore Forest: a perfect rock by the river. He even tumbles part of the way there But when he arrives, there's a grumpy little monster sitting there. Tumblebee tries everything he can to make the monster smile. Nothing works . . . until he remembers the power of friendship.