Inoculation Day: It is Inoculation Day at Charles Darwin Middle School. Unlike his old school, Nurse Gazelle shoots the shots with a pea shooter. She shoots a tiger and Assistant Coach Ferret tags him. Jake says he freaks out at the sight of the needle. Jake accidentally slips on a banana and winds up on a skateboard, and he rides on the skateboard and swings on a vine. Nurse Gazelle shoots the shot. Adam pops up and it hits him in the shoulder. He reads the shot while Principal Pixiefrog tags him. It says it may cause an adverse side effect in humans. He immediately starts scratching himself and asks Jake for a banana. Jake gives him a banana and he devours it. Adam starts acting like a monkey and he swings on a vine. He grows fur and throws his pants at Jake. He swings to the cafteria and Pixiefrog calls a faculty meeting. Them and Jake chase Adam and he Jake threatens Adam. He burps, Sending the whole faculty down the hall. After searching for hours, they wind up meeting Adam in the boys bathroom. The principal runs away, but falls into a mop which makes him look like a girl. Adam busts out of the school holding him and climbs Ingrid. Jake climbs right up with him and an orginization called B.A.A.A. arrives and says they are endngering animals. When Jake climbs up and the nurse can't figure out which one to hit with the shot. She fires, and its off course, but Jake reflects it with his butt, turning Adam back to normal. At the end, the nurse says that it wasn't just the shot, It was Jake's butt.