After a particularly hard history test, which even Jimmy found challenging, Sheen claims to have found it easy. Suddenly Ms Fowl calls him back, which Sheen thinks is to compliment his test. However, it turns out that Sheen has failed, and needs to ace the maths test to avoid being kept back.
Sheen begs Jimmy to help him, saying that he cannot be held back AGAIN. Jimmy agrees, and him and Carl set to work. They try to get him to pay attention through negative-reinforcement, giving him a zap every time he is distracted. Despite this, he still cannot concentrate, and soon he seems doomed. Jimmy finally decides to turn his 'brain-drain' helmet into a 'brain-gain' one.
It works well, and Sheen becomes a genius. He easily aces the maths test, getting all the answer correct. But his brain keeps growing, and when Jimmy asks him to get his intelligence sucked away, he uses some acquired telepathic powers to throw Jimmy off. Then he declares himself the supreme ruler, and takes Libby as his queen.