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Whether it's Howie Mandel appearing as himself or Jim's stand-in in The Office, some single-episode TV characters deserve more screen time.

One of the essential components of good television is a solid cast of characters. Audiences want people they can root for or against, and invest in. Whether it's Homer Simpson, Uncle Phil, or any other core cast member, there are people whom the audience relies on for consistency.

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Conversely, the main cast members are just a single ingredient, and countless cameos and no-name bit parts are intrinsic to the viewing experience. In several instances, one-off characters have left a long-lasting impression on viewers, and deserve recognition for their brief but brilliant moments.

In the ninth season of It's Always Sunny In Philadelphia, the gang (and viewers) are introduced to Mac's cousin from the countryside, appropriately referred to as Country Mac. At first, Country Mac appears to be little more than a carbon copy of his Philly counterpart. Later on, however, it's revealed that he's almost the complete opposite.

Country Mac demonstrates his bravery by jumping off a high bridge when his cousin (a self-proclaimed badass) is too scared, and performing a perfect "ocular pat-down" of an attacker before he can pull a knife on the gang. Finally, while Philly Mac is a hypocritical homophobic closeted gay person, Country Mac, who is also gay, is open and incredibly proud of his sexuality.

In the acclaimed The Simpsons episode, "You Only Move Twice," Homer is offered a job working for Hank Scorpio, the eccentric CEO of Globex Corporation. From the moment Scorpio makes his first appearance, he cements himself as an iconic character, thanks to the improvisational comedy skills of voice actor Albert Brooks.

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Every single scene featuring Scorpio is ripe with clever jokes and quips that fire off at a rapid pace. As the episode progresses, it's revealed that he's not just a quirky, silver-tongued business owner but a ruthless and evil genius moving toward world domination. The last time the audience sees him, he's gleefully roasting a group of soldiers with a flamethrower while laughing maniacally.

In the cold open of The Office episode, "Andy's Ancestry," Dwight is shocked to find that his desk-mate Jim is replaced by an Asian man (played by Randall Park) who claims to be Jim. In actuality, he's an actor friend of Jim and Pam's named Steve, who agreed to the prank while Jim was at the dentist's.

Despite Dwight's insistence that he's not really Jim, Steve proves him wrong by showing a picture of himself with Pam and the kids, giving Pam a kiss, and even flawlessly reciting Jim's recent sales history. Park's performance sells the entire scene, largely due to his uncanny ability to mimic John Krasinski's role as Jim perfectly.

Parks and Recreation is no stranger to odd characters, but very little manage to live up to Park Ranger Carl Lorthner. In the episode "Park Safety," Leslie enlists Carl's help to improve the safety of Pawnee's local parks after Jerry was supposedly mugged. The one downside of working with Carl (played by Andy Samberg) is that he has a small problem with controlling the volume of his voice.

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What makes Carl such a great character isn't just his tendency to yell everything he says; it's also his timeless quotes. Some notable sayings include, "You might not be so confident once you've walked a mile in my size sevens!" or, "You guys got any snacks?"

South Park's "Asspen" episode is a brilliant satire of the classic underdog sports film. The kids and their families head up to Aspen to enjoy some time on the mountain, and they find themselves meeting an array of characters like stereotypical jocks and pushy timeshare salespeople. The one character who sticks out, though, is the ski instructor, Thumper.

Thumper seems like a decent guy who legitimately enjoys what he does, but tends to oversimplify the process. He repeatedly reminds the kids to utilize two techniques to control their skis: pizza and French fries. Thumper proves to be a valuable ally when he assists Stan in becoming a proficient skier to beat Tad in the upcoming race.

Superstore's third season kicks off with Cloud 9's reopening after a devastating tornado. The store hires comedian Howie Mandel (making an appearance as himself) to perform. When he arrives, he meets Dina, who assumes he's a regular employee and assigns him some busy work to get the store ready.

The highlight of Mandel's appearance is when Glenn has to stall in front of a crowd while the store gets ready. He asks if Mandel can do a stand-up routine, but the comedian explains how he was booked by his appearance agent and not by his performance agent, meaning he can't tell jokes. When Glenn asks if he can at least tell other people's jokes, Mandel responds with a flat "No."

Some people love Carrot Top, and others hate him, but regardless of their feelings, it's hard to deny that he has a great sense of humor when it comes to poking fun at himself. Carrot Top appears in season four of Reno 911! playing a grossly exaggerated version of himself running amok in a hotel room.

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In real life, Carrot Top has shown himself to be easygoing and doesn't take himself seriously. In the show, he demonstrates what happens when a gimmicky comedian loses their mind. He ends his appearance by stealing one of the deputy's guns and patrol vehicles and booking it, but not before pretending to pay off his hotel damages with a rubber check.

Hey Arnold! showed children all the colorful characters that can be found in the city. There were many one-shot characters throughout the show's run, but one that deserves extra attention is Stoop Kid.

Arnold and his friends initially see Stoop Kid as a territorial bully who refuses to let people so much as look at his stoop. Later on, however, Arnold discovers that Stoop Kid is actually terrified of even stepping off his steps (strongly hinting that he may be dealing with agoraphobia). By the end of the episode, Stoop Kid overcomes his phobia and vows to use his newfound abilities to harass people on and off his stoop.

Family Guy's Peter decides to pursue one of his lifelong dreams of becoming a Renaissance Fair jouster. During training, he meets the man who once saved his life: the Black Knight (voiced by Will Ferrell). While Peter remembers the Black Knight as a hero, it turns out he's actually not that friendly. What follows is a series of embarrassing encounters where Peter continues to annoy his idol.

One of the best gags in the episode is when they're in the bathroom, and the Black Knight is seen shaving with his helmet on. Peter distracts him, causing "BK" to nick himself, so he places a piece of tissue on the wound... on his helmet.

The final episode of The Good Place takes place in the titular location and shows the main characters enjoying paradise. Tahani, in particular, has a list of goals she wants to complete now that she has unlimited time and resources, and one of those is becoming a master at woodworking. Who better to teach her woodworking than Nick Offerman himself?

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Offerman, an avid woodworker, and craftsman, essentially gets to portray a version of himself doing what he loves most, even after he has passed. Another theory to this appearance is that he's actually playing Parks and Recreation's Ron Swanson, who also shares Offerman's love for woodworking.

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Award-winning fantasy/children's book author with a love for pizza, comics, and shenanigans.