In this whimsical episode, Peabody and Sherman travel back in time to meet the renowned scientist Louis Pasteur. However, they encounter a peculiar problem: Pasteur's cow has developed a case of amnesia and believes she is a chicken. Determined to help, Mr. Peabody devises a series of humorous experiments and remedies to restore the cow's memory. As they navigate the challenges of farm life, the episode highlights Pasteur's groundbreaking work in science while showcasing Peabody's cleverness and the lighthearted antics that ensue.