

Ickis, Krumm, and Oblina are saddled with babysitting the Gromble's nephew, Bomble. They take him along on a garbage hunting trip to a local hospital where the baby monster is accidentally switched with a new-born human baby. The trio must track down the Bomble at the home of his new human ""parents"" and replace him with the human.
The festival celebrates the shedding of skins that each monster must undergo as he or she moves from childhood to adolescence. As the festival approaches, Krumm is chosen to form a band and Oblina is chosen to perform the festival's ceremonial dance. Ickis, who shows no signs of shedding, feels left out.
Ickis, Krumm, and Oblina sneak into Simon's house to scare him. After the scare, Simon seems to know the monsters' whereabouts. He shows up when they least expect it. How is he doing it?