Although Season 19 features great moments in “The Debarted” — a spoof on “The Departed” — it suffers from the infamously bad episode “That ’90s Show.”

The episode needlessly replaces much of the Simpson family’s history, placing Marge and Homer’s initial romance in the 1990s, confusing fans and critics alike.

Season 17 has little in the way of originality and jokes, but it gives some extra attention to side characters, like the Grandpa-centric episode “Million Dollar Abie.”

“Treehouse of Horror XVI” continues the show’s tradition of spoofing horror franchises, like “B.I. Bartificial Intelligence,” where the family replaces Bart with an android.

While it doesn’t have a whole lot going for it, Season 18 does contain many notable guest stars, such as Metallica, Joe Mantegna, Joe Pantoliano, and Michael Imperioli.

The standout episode is “24 Minutes,” a parody of “24” that even features Kiefer Sutherland and Mary Lynn Rajskub reprising their roles as Jack Bauer and Chloe O'Brian.

Despite a few good episodes, Season 20 is best remembered for hitting a milestone: tying with the “Gunsmoke” record of most seasons on the air.

“Homer and Lisa Exchange Cross Words” feels like a call back to the classic feel-good era of “The Simpsons,” though the season’s standout episode is “Sex, Pies and Idiot Scrapes.”

Season 16 provides some good episodes that altered the show’s canon, including “There’s Something About Marrying,” which reveals that Marge’s sister Patty is a lesbian.

Other notable entries are “Homer and Ned’s Hail Mary Pass,” where Ned Flanders makes brutal yet accurate films based on the Bible, and “Future-Drama,” a flash-forward episode.