Brother From Another Series - S8-E16
Question: In this episode, Sideshow Bob seems to no longer want to kill Bart (shown by his happiness at seeing him near the dam, and later on, saving his life, as well as Lisa's). But in episodes after this e.g. "Funeral for a Fiend" and "The Great Louse Detective", Bob suddenly wants to kill Bart again. What caused him to change his mind after this episode? It can't be because he thinks Bart is responsible for sending him back to jail because in this episode when Bob and Cecil get arrested, Lisa defends Bob and says he had nothing to do with it, and Lou even backs her up by saying that Cecil confessed to the whole thing.
Chosen answer: While Sideshow Bob does rescue Bart, he never is truly over his hatred of him. At the end of "Brother From Another Series", Cecil is actually able to trick Bob into swearing revenge on Bart, which is why Bob is sent to prison despite being innocent of trying to blow up the dam, and Bart is once again his nemesis. Although time rarely passes in the show (i.e. Bart stays 10 for the most part), it's not until season 12 when Sideshow Bob appears next, and it's clear he's been in prison the whole time, with plenty of time to rebuild his anger and hatred over Bart (and Krusty).
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