Between the Lions

Why the Baboon's Balloon Went Ka-Boom! (2x18)

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Theo wants to teach the cubs a lesson, which he finds in a book of concatenations called Because a Little Bug Went KA-CHOO! What Theo doesn't know is that, by pulling that book from the middle of a pile, a pen dropped to the floor, setting off a concatenation in the library. It culminates with a hot-air balloon's bursting.