Panda and Clifford are having a fun time together when Clifford realizes Panda is using him to get close to his sister, Lucy. While running away from Panda, Clifford accidentally gets peanut butter all over himself, and he experiences a severe allergic reaction, causing his face to swell and his breathing to slow. Panda looks for the allergy pen to save Clifford and experiences a similar allergic reaction. Despite his condition, he manages to save Clifford, who in turn saves him with another allergy pen.
The Peanuts help the Wright Brothers set up their flyer for another test drive in hopes of beating their past records. One of the Peanuts explains to Charlie Brown how their first flight went and how they decided who would fly first. The Peanuts also explain how the Wright Brothers pilot their glider.
Hank explains the different types of fat (saturated, unsaturated, omega-3, trans) that exist and illustrates their molecular makeup. He uses a jar of peanut butter to relate his explanations to the real world.