Sheldon and Stephen Hawking begin playing a popular online game Words with Friends. When he stops responding to their game, Sheldon begins obsess about being ignored. Meanwhile, Penny goes back to school by taking a history class at the local community college. First she doesn't tell Leonard about it. After he finds out about it, he rewrite her paper while she was asleep making her mad. Penny wants to prove that she is more than a waitress.