Bart and Millhouse attends a Spinal Tap concert. After viewing the show he decides he wants to be rock star. Homer and Marge decide that they should buy Bart a guitar to encourage him musically.
Meanwhile, Otto crashes the school bus and because he doesn't have a license, he is banned from driving the bus until he gets one. He is kicked out of his apartment and Bart invites him to stay in the garage, without asking his parents.
Otto plays Bart's guitar since Bart is bad at playing himself. Homer orders Otto to leave, so he tries to take the driving test again. Otto tells Patty and Selma how much he hates Homer and they pass him, even though he did badly.