The Simpsons: 8 Episodes From The Bad Seasons You Need To Watch
4. Gone Boy
Sideshow Bob returned in Season 29, which barring a non-canon Treehouse appearance made it his first in the show for 4 years. That episode was typically thought of as his worst appearance to date, so there was a lot of pressure on it to deliver. Considering this was shortlisted for an Emmy, it certainly did the job.
Gone Boy avoided the first mistake of many newer episodes by refusing to get bogged down; there are no real B-plots here. Bart falls down a hole in the woods, winding up in a military bunker. From there, we get some amusing scenes as Bart deals with the isolation admirably, but on the surface, he's presumed dead as several search attempts fail.
Bob's reaction to the news though is the most interesting. After making it his mission to kill Bart, hearing that he is gone feels hollow when he didn't get the strike the killing blow. Segments with Bob's prison therapist has a sequence that goes dark for this show, with reality breaking as we see splices of Bob's obsession. Bob does eventually find Bart, but ultimately fails to kill him.
It's funny throughout and well paced too, with Homer and Grampa still a classic match-up.