Drew and the Motorcycle - S6-E19
Plot hole: In this episode, Drew acts like he is "Kyle", an alter ego he creates once he gets a motorcycle and starts to date the insurance agent who stops by. During the scene where the insurance agent, Drew, Lewis, and Oswald are in the kitchen, Lewis grabs the pan to hit the insurance agent over the head and Drew fights with him, Lewis responds "Drew" and the scene goes on normally. Lewis calls Drew Drew, not Kyle, as he is supposed to be called. If the insurance agent had heard him be called Drew, she would have known it was Drew, and not Kyle, all along.
Answer: "That Thing You Don't" (s03e10). The gang forms their old band again for a talent contest. Lewis is on drums, Drew is on trumpet, Oswald is on trombone, Kate is lead singer.
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