Template:Spoilerstart The episode begins with a virus army on Gumball's fur. The leader of the army rallies the troops, giving an inspirational speech about how they will use Gumball's body as a stepping stone to their ultimate goal of infecting everyone in the world. As they charge towards Gumball's nostrils, the ground beneath them shakes. The cause of this sudden movement is Teri attempting to force Gumball to wash his hands in the water fountain. After learning why he refuses to wash his hands (as well as his disturbing method of showering without his hand getting wet), she is able to overpower him and finally clean his hands. The screams of the virus army as they are washed down the drain can be heard, but Gumball dismisses it as nothing. After the three of them leave, it is revealed that the leader of the virus army has survived, and he plots vengeance for his fallen comrades.
Later that day, the class does computer work at the library, though most of them use the time to play Space Invaders. Gumball and Darwin, unaware that Teri is right next to them, begin to mock her obsession with cleanliness. She announces her presence, angrily, causing the two of them to apologize. Then she uses Gumball's computer to show them a picture of a finger that hasn't been disinfected after a paper cut. Gumball and Darwin reel back in horror at the disgusting picture. Darwin, suddenly afraid of germs, grabs some of Teri's disinfectant substance and rubs it all over his body. Gumball, on the other hand, remains nonchalant about germs, mocking their fear of it and dismissing germs as a part of life. Teri counters with the fact that keyboards generally have more germs than a toilet seat. Gumball sighs and begins licking the keyboard in a show of defiance. Unfortunately, the vindictive virus was on the keyboard, waiting for an opportunity to infect Gumball, and his exposed tongue was just what he was looking for. He gets sidetracked by the various bacteria that were also on the keyboard. Unwilling to let them infect Gumball instead of him, he fights them all off. Just as he finishes the last one, Gumball finishes licking the keyboard, causing him to scream in exasperation.