Gobo's come down with the Pebble Pox, so it's up to Boober and Wembley to go to the Cave of Shadows to get Gobo's cure. However, Boober's not too fond of the idea, and shares his worries with Wembley along the way. Before long, Wembley comes up with a bad case of the Pebble Pox, too. Will Boober leave his sick friend behind and ditch the journey, or will Boober put his germ-worries aside to help his friends?