The kids are having a sleepover and the mayor tells them a bedtime story about a baby troll. Ziggy decides he wants a pet troll so the kids venture into the mountains and find a troll named LuLu who begins to eat all of the sports equipment. Much to Robbie's delight, he disguises himself as a troll catcher as he thinks a bigger troll will eat more sports equipment but will the kids be able to return LuLu back home before she eats most of LazyTown?