The guy that Howard knew who could get the liquid helium, that was in short supply, needed by Sheldon and Leonard for an experiment. His name was Kenneth Fitzgerald and although he talks tough, he was intelligent and able to discuss their superfluid theory and debate "Ernest Goes to Jail". That movie scared Sheldon straight and he hopes it will do the same for Kenneth who is willing to change. Kenneth mentions that he has a daughter, and that whenever she has a sleepover, she and her friends tend to scream a lot and listen to Katy Perry.