Like a bedtime story on acid, or a Chuck E. Cheese restaurant that’s been commandeered by teen ravers, this bewildering musical follows a once-popular band of bears who stage a reunion concert. Because the movie is “inspired” by a Walt Disney World attraction, in which stiff, animatronic bears play tinny music, our heroes have the distinct look of mounted animal heads that have been plopped onto a man in a fur suit. I’m sure kids won’t question any of this, but when the bears began to fly for no apparent reason, I started to suspect someone had spiked the water bottle I brought into the theater.