Warning: Spoilers for The Simpsons season 34, episode 7.

While The Simpsons has a huge and much loved cast of supporting stars, the series keeps making the same mistake with its characters. The Simpsons has one of the biggest casts in television history. Thanks in large part to the show’s thirty-five years on the air, The Simpsons has amassed a veritable army of supporting stars.

However, The Simpsons can’t keep relying on random minor characters to hold entire episodes together. On occasion, it works. For example, Simpsons season 34’s parody of Stephen King’s IT saw Krusty the Clown get as much screen time as any of the titular family, but this worked since the iconic character served as a perfect parody of Pennywise. That said, focusing episodes on side characters who cannot sustain a full outing is a major mistake that The Simpsons has too often relied on in recent seasons. Unfortunately, this issue came out in full force in The Simpsons season 34, episode 7, “From Beer to Paternity,” as the series tried to base a plot line around Duffman, a deservedly under-developed side character.

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The Simpsons Duffman Episode Didn’t Work

Every way Duffman has died

The plot of “From Beer to Paternity” did not have much in the way of compelling stakes, but this was not a major surprise. Since Duffman was always a one-note joke character, basing an episode on his strained relationship with his estranged daughter was always going to be a hard sell. Much like The Simpsons' Babadook parody was really about Marge’s dissatisfaction with her lot in life, “From Beer to Paternity” did use its story to interrogate Homer's relationship with Lisa by contrasting his seemingly solid parenting with Duffman’s absence. However, this alone wasn’t enough to justify the episode’s existence.

Why Spotlight Episodes Fail For The Simpsons

Homer admonishes Duffman in The Simpsons season 34 episode 7

Episodes of The Simpsons that focus on a minor supporting character tend to just point out how limited the role and potential of these characters are. From season 23, episode 12, "Moe Goes From Rags to Riches," to season 32, episode 14, "Yokel Hero," to season 26, episode 1, "Clown in the Dumps," many of the lowest-rated episodes of The Simpsons are adventures that focus on background characters but fail to make them compelling. Ironically, the canceled Simpsons spinoff "Springfield" would have followed this same formula, but that show might have succeeded since it would not have needed to also incorporate the eponymous family.

The problem with episodes like "From Beer to Paternity” is that they either outright ignore the Simpsons themselves or awkwardly cram them into another character’s story. When The Simpsons ignores the Simpson family, the show loses a central part of its appeal. When the Simpsons play a major role in a supporting character's spotlight episode (like Homer and Lisa’s part in reuniting Duffman and his daughter), this leads the viewer to wonder why The Simpsons bothered focusing on a minor figure like Duffman in the first place. In contrast, The Simpsons IT spoof worked because Krusty was just the villain, not the main character.

The Simpsons Keeps Wasting Impressive Cameos

Krusty-the-clown-drew-barrymore-simpsons-cameo

“From Beer To Paternity” was never sure who its main characters were. Were they Duffman and his daughter, or Homer and Lisa? If it was Homer and Lisa, they didn’t learn anything that they hadn’t been through hundreds of times before. If it was Duffman and his daughter, they lost a lot of screen time to, understandably, the Simpson family. This imbalance becomes more noticeable and tough to excuse when The Simpsons enlists the help of impressive guest stars, only to waste them by underutilizing their characters. In “From Beer to Paternity,” Aubrey Plaza played Duffman’s daughter Amber, but The Simpsons gave the sitcom veteran little to do.

Related: The Simpsons Fixed Pennywise’s Terrible It: Chapter 2 Death

While The Simpsons season 34’s celebrity cameos haven’t been as pointless as some earlier outings, Plaza’s appearance was still a case of wasted potential. An independent artist who wasn’t sure about reconnecting with her father, the sardonic Amber could have struck up a friendship with Lisa as the pair bonded over their flawed fathers. She could have been given a compelling reason to give Duffman another chance instead of him saving her life in a rushed deus ex machina. However, this would have drawn attention away from Lisa and Homer and made the entire episode about Duffman, meaning viewers expecting to see the show’s main characters would be let down. Thus, The Simpsons season 34 once again proved that episodes centered around minor supporting stars rarely work for the series.

New episodes of The Simpsons air on Fox on Sundays.

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