Power Pack descend into the NYC sewers to rescue a kitten. While there, they are nearly drowned by the rushing water currents and the alligators they discover. The team - and the kitten - make it out in one piece, but two mistakes will come back to haunt them later. First, Julie insists on washing the costumes because they have been in the sewer; inadvertently breaking the costumes' communication links to their smartship, Friday.
Second, they leave their backpacks and schoolbooks, with their names and addresses, in the sewer by accident. They are discovered by Piper, one of the Morlocks.