Donatello is in his lab working on a chemistry project. Talking to himself, he muses that scientists are neither "glass half empty" nor "glass half full," because they know that the proverbial glass is already completely full—with half liquid and half gas. Donnie hasn't had a chance to refocus on his work when he realizes someone his prowling behind his chair. It's Raphael, who announces he's bored and pulls Donnie into a friendly headlock. Donnie barks at Raph to get out, and Raph decides it was foolish to think he could go to Donnie to find some fun.