Thinking that the world is chaotic enough as it is, Eris, the goddess of chaos, decides to quit chaos to work at a hamburger restaurant. Then, she entrusts Grim the Apple of Discord to watch over for her, which he seals in his old trunk. However, the apple frees itself from the chest and goes to Billy. Later, Mandy is attracted by the apple's powers, and after being persuaded by Billy's talking burrito, Billy, Mandy and Grim battle for control of the apple, which divides in three pieces. In the end, the battle results in them being fused together into an amorphous mass, and, with an evil grin on her face, Eris decides to offer the apple to Irwin too. This episode is unusual in some aspects: it starts being called Billy gets Dumber, but then the Apple of Discord swallows the screen and the real title Complete and Utter Chaos is shown instead; the episode starts at the end, and the story is told as a flashback; the talking burrito is featured prominently, but other than a brief mention, its origin is not explained.