Stan realizes his own weight problem after he criticizes Steve about his new, overweight girlfriend, so he goes overboard with exercising, and develops anorexia. Steve realizes that his overweight girlfriend is the root of his father's problems, and he has to make a hard choice in an effort to save his father's life.

While researching a paper about George Washington Carver in celebration of Black History Month, Steve uncovers a conspiracy that's been going on since the Civil War. When the curator of the Smithsonian Peanut Museum reaches out to tell Steve the truth, he's mysteriously murdered, and Steve and Stan are tracked by a secret society that will stop at nothing to keep this scandalous secret of American history.