Spongebob Squarepants - Mrs. Puff's Hat
Go to the part where Spongebob and Patrick are in the chili inside the cafeteria in the episode where Mrs. Puff goes to jail. When Mrs. Puff says "I don't have to worry about uranium in the water supply," and drinks a glass of water, her hat turns from red to black and then back to red. Her hat is only black as she drinks the water, so look carefully.