The Simpsonshas seen literally hundreds of characters come and go over the years. Some of them are lasting, recurring characters, while some have only made brief appearances, some for the purpose of a single joke.
Whatever the reason for their appearance, their addition to the episode only makes things funnier. Even though these characters only appear in one episode, it certainly hasn’t stopped fans from hoping they’ll see more of these memorable faces at some point in the future.

10Groundskeeper Seamus – ‘I Am Furious (Yellow)’
Season 13, Episode 1 (2001)
Seamus (Karl Wiedergott) is an Irishman who is hired to help keep the grounds at Springfield Elementary, only to be fired, for which he blames Groundskeeper Willie (Dan Castellaneta). In a strikingly poignant metaphor, Seamus and Willie have a brutal brawl, which ends with Willie emerging the victor.
RELATED:‘The Simpsons’ Characters, Ranked by LikabilityThough his only appearance is for a brief gag, it’s a pretty good one. This makes him one of the more underrated characters to appear in the show, and one that deserves to be seen more. After all, his dynamic with Willie certainly is interesting.

9Guy Incognito – ‘Fear of Flying’
Season 6, Episode 11 (1994)
Guy Incognito (Dan Castellaneta) only makes a brief appearance for a short, (albeit hilarious) joke. His name and appearances give off the impression that he is obviously just Homer in a bad disguise. Things quickly become apparent however, that Guy Incognito is actually a legitimate person who just happens to look a lot like Homer.
This striking resemblance ends up getting him into significant trouble after he walks into Moe’s (Hank Azaria) Tavern and is beaten up by the patrons who mistake him for Homer.

8Larry Burns – ‘Burns, Baby Burns’
Season 8, Episode 4 (1996)
Season 8 saw a plethora of characters who only appeared once and were never seen again. One such character is Larry Burns (Rodney Dangerfield), who is the long-lost son of Montgomery Burns (Harry Shearer). He’s not the sharpest tool in the shed, but he is able to recognize his own father when he sees him.
They first meet when Monty passes by his son’s gift booth in a train. Larry recognizes the same birthmark that they both share and gives chase. In time, Monty comes to realize that Larry is indeed his son. As stated, Larry isn’t very bright, and he’s socially inept. But it’s his awkwardness yet well-intentioned attitude that makes him lovable.

7Zia Simpson – ‘Holidays of Future Passed’
Season 23, Episode 9 (2011)
Zia Simpson (Nancy Cartwright) is the future daughter of Lisa Simpson (Yeardley Smith) and MIlhouse van Houten (Pamela Hayden). Despite being the child of two intelligent individuals, she has a snarky, rebellious attitude. This is quite something considering the fact that Zia is genetically engineered using only the best genes between the couple. That is to say, she is 100% made up of Lisa’s DNA.
Still, her appearance and personality, as well as her obsession with being online have made her quite a memorable character. She has appeared several times in other works of media, but only once in an actual episode of the show.

6Beatrice Simmons – ‘Old Money’
Season 2, Episode 17 (1991)
Beatrice Simmons (Audrey Meadows), commonly referred to as “Bea,” is Abe Simpson’s (Dan Castellaneta) girlfriend whom he meets at the retirement castle. They seem to maintain a good relationship, but unfortunately, their love story is one that would end in tragedy. You see, Homer doesn’t believe Bea is actually real and insists she must be some delusion fabricated by his father. So he takes Abe out places to keep him occupied, causing Abe’s dates with Bea to fall through.
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One evening, when Abe gets home from an exasperating day with his son, he returns happily, eager to see his love. Sadly, he is informed that Bea has died of a burst ventricle. Abe states that the burst ventricle may be the official cause of death, but he knows that she died of a broken heart after he unwillingly stood her up. Bea’s story is one that is a tragic reminder to take the elderly seriously and to visit them as often as you’re able to, because you never know what could happen. It is not Bea herself that makes her memorable, but rather, her story.
5Lyle Lanley – ‘Marge vs the Monorail’
Season 4, Episode 12 (1993)
So Lyle Lanley (Phil Hartman) technically appears in two episodes, however, the second of these is a clip show episode with recycled footage from the original, so it still counts. This charismatic character is a monorail developer and salesman with one heck of an ear for music.
He convinces the people of Springfield to build amonorailby way of a choreographed song and dance, and a catchy one at that. It’s one of the standoutSimpsonsmusical numbers, and it’s the reason this character in particular is so memorable.
4Penelope Owsley – ‘Once Upon a Time in Springfield’
Season 21, Episode 10 (2010)
Also known as Princess Penelope (Anne Hathaway), this character is a singingDisney-esque princess who is brought onto Krusty’s (Dan Castellaneta) show in an effort to add diversity to its all-male cast. Penelope sings songs and pulls off elaborate performances which boost the show’s rating and quickly overshadow Krusty.
Despite this, she and Krusty wind up falling in love, and Krusty can be seen at his happiest. It’s a breath of fresh air from the cynical, grumpy, thieving attitude the clown usually has. They then make the show a joint effort, performing musical numbers together, which is nothing if not adorable. Sadly, Penelope moves away to France after their relationship falls apart, but is still seen reminiscing about the clown she loved so much. Apart from a few minor background cameos in other episodes, she only really appeared in the one.
3Frank Grimes Jr. – ‘The Great Louse Detective’
Season 14, Episode 6 (2002)
Frank Grimes Jr. (Hank Azaria) is the son of another fan-favouriteSimpsonscharacter, Frank Grimes (Azaria). Frank Grimes initially only appeared in one episode in Season 8, where he met a swift demise after accidentally electrocuting himself. The cause of his untimely death is the end of a chain reaction of events that begins with Homer. Still, Grimes Sr. has appeared in a couple of episodes since, but his son has only appeared in one.
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Bearing the exact same likeness and vengeful attitude, Frank Grimes Jr. seeks revenge on Homer for causing the death of his father. This results in the son becoming a mechanic by day and an aspiring murderer by night as he tries desperately to find ways to end Homer’s life. Thankfully, he isn’t very successful. Perhaps he should stick to fixing cars.
2Hugo Simpson – ‘Treehouse of Horror VII’
Season 8, Episode 1 (1996)
Hugo Simpson (Nancy Cartwright) is Bart’s (also played by Cartwright) identical conjoined twin. He has only ever appeared in aTreehouse of Horrorepisode, which makes his entire existence non-canon. That said, he’s still quite a lovable character even though he is initially portrayed as a monster.
Initially, Marge (Julie Kavner) and Homer have Hugo imprisoned in their attic due to the fact that Hugo was born as an “evil” twin. Later, it is revealed that Hugo is actually the good twin, and Bart is the evil one. Hugo may be a little strange because he’s been kept away from the world and fed nothing but fish heads, but his intentions are pure. All he wants is for him and Bart to have a (conjoined) relationship again, and for his family to accept him.
1Hank Scorpio – ‘You Only Move Twice’
Season 8, Episode 2 (1996)
Hank Scorpio (Albert Brooks) becomes Homer’s temporary boss when Homer moves his family to Cypress Creek. Hank owns the Globex Corporation, and despite being a Bond-esque supervillain, he’s one of the most good-natured people on the show. Homer puts forth several ridiculous ideas, but Hank never laughs at him or berates him, and takes all of his ideas into consideration.
On top of that, Homer actually becomes quite the worker under an inspirational leader, and he develops a fast friendship with Hank. Despite making a couple of brief background or intro cameos, this character remains a fan favourite despite only really being in one episode.
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