Tony Hawk checks into the Tipton; Maddie and London has a crush on their fencing instructor. While Zack and Cody are doing their science project, the problem is that Cody has a fear of germs, and when Zack makes a mistake when analyzing a germ from the kitchen and thinks it's a toxic type of black mold, the rumor spreads through the hotel and everyone starts panicking. Cody gets over his fear after he realizes that he can't go skateboarding with Tony Hawk wearing an anti-germs suit.