Top 10 Character Introduction TV Episodes

When a television show introduces a new character or two, it's usually a flip of the coin. They can be a game-changer or a game-wrecker.

Some episodes introduce a new character that changes the show so much, you wonder how the show functioned without them. Other new characters, however, are given a lukewarm reception and are subsequently written out of the show as if they never existed.

In this list, we'll be going over some of the most iconic episodes that introduced new characters, for better or for worse.

The Top Ten

Steve Urkel in Laura's First Date - Family Matters

Steven Quincy Urkel is a fictional character from the American sitcom Family Matters, which aired on ABC and later CBS. Portrayed by Jaleel White, he was originally intended to appear in only one episode. However, he became the show's most popular character and eventually the central figure.

When it comes to the epitome of nerdiness, there's really no topping Steve Urkel from Family Matters. Played by Jaleel White, Urkel was actually designed to be a one-time character played for laughs but proved so popular that the writers eventually made him a permanent character and eventually the face of Family Matters. He was so popular, he even got his own breakfast cereal and a doll of some kind.
Of course, Jaleel has no intention of reprising his role in any live-action format. The last time he reprised his role was in the episode "When Urkel-bots Go Bad" in "Scooby-Doo and Guess Who?" Feel free to reply to this if there's any solid news of Jaleel playing Steve in any future animated roles.
Tommy Oliver in Green with Evil - Mighty Morphin Power Rangers

Tommy Oliver is a fictional character and a central figure in the Power Rangers franchise. He debuted as the Green Ranger in Mighty Morphin Power Rangers and later returned in several series as the White, Red, and Black Rangers. He is one of the most enduring and popular characters in the franchise's... read more

After a few episodes of the show, Jason David Frank plays the iconic Tommy Oliver in this 5-part epic where Rita Repulsa makes him the Green Ranger after he proves his martial arts skills equal to Jason's. While Tommy proves to be more than what the Rangers can handle, they discover that the Sword of Darkness is what's keeping him under Rita's control and destroy it, freeing Tommy and allowing him to join the group as the Green Ranger.
But Rita eventually uses the green candle to rob Tommy of his powers, forcing him to give his coin to Jason. The reason for this was so that Jason Frank could play a protagonist in another Saban show, VR Troopers. However, Tommy proved so popular that he returned in "Return of an Old Friend Part II" and has been a staple of the show all the way up to "Passing the Torch Part II" in Power Rangers Turbo. He even returns in Power Rangers: Dino Thunder, proving to be one of the most popular characters in the Power Rangers mythos.
Sailor Uranus and in Driving Dangerously - Sailor Moon S

In the original Japanese version, the episode is called "A Handsome Boy? Haruka Tenoh's Secret" and it introduces two new sailor senshi in the series: Sailor Uranus/Haruka Tenoh and Sailor Neptune/Michiru Kaioh (or Amara and Michelle in the English dub, respectively). Even though Sailor Moon and the other Sailor Senshi are after the same goal, these two have no qualms about sacrificing human life, and this doesn't jive well with the others.
Uranus and Neptune were also notable for being a lesbian couple, something which was removed from the English dub, upsetting many fans. In the dub, they were portrayed as cousins, which felt wrong on too many levels. Thankfully, we now have the option of watching Sailor Moon in all its unedited glory.
Joe Swanson in A Hero Sits Next Door - Family Guy

Joseph "Joe" Swanson is a main character on the animated television series Family Guy. He is portrayed as a paraplegic police officer who is tough and determined, often participating in physical confrontations despite his disability. Joe is voiced by Patrick Warburton and has been a regular character... read more

When Family Guy made its debut, there were definitely some similarities between it and The Simpsons. But Family Guy was to The Simpsons as Mortal Kombat was to Street Fighter II. They share some similarities, but the former was for the older crowd. Not to mention its cast of characters is more wacky, such as Joe Swanson (voiced by Patrick Warburton), a police officer confined to a wheelchair after a supposed attempted robbery at an orphanage.
After Peter accidentally takes out the ringer for the "Happy-Go-Lucky" Toy Factory's baseball team, Mr. Weed demands Peter find a replacement if he wants to keep his job. He finds one, only to discover that he's confined to a wheelchair. But to everyone's surprise (and Peter's chagrin), Joe ends up winning the game. As the show continued, Joe has been more capable than most police officers despite being unable to use his legs, proving that the term 'disability' is just a state of mind.
Sideshow Bob in Krusty Gets Busted - The Simpsons

Dr. Robert Underdunk Terwilliger, better known as Sideshow Bob, is a recurring character in the animated television series The Simpsons. He is voiced by Kelsey Grammer and is most often portrayed as the sophisticated and vengeful nemesis of Bart Simpson. Sideshow Bob was originally Krusty the Clown's... read more

While Sideshow Bob was first seen in "The Telltale Head", this is the episode where he makes his speaking debut as Bart's eternal nemesis. Voiced to perfection by Kelsey Grammer, Sideshow Bob really made an impact in this episode. Tired of being in Krusty's shadow, Bob decides to frame him for armed robbery so he can become a star in his own right. After Bart and Lisa expose him, Bob develops a deep-seated hatred not just for Bart, but for the rest of the family over the course of the series.
Even though he doesn't appear regularly, that's part of what makes him so special, as he definitely makes an impact in each episode where he's one of the main characters. It looks like he'll continue to make appearances as long as Kelsey Grammer is still able and willing to provide his voice.
Harley Quinn in Joker's Favor - Batman: The Animated Series

Batman has had a sidekick since 1940 when Robin debuted in Detective Comics #38. So why not give the Joker one? Surprisingly for some people, Harley never appeared in any comics until her debut episode, and it pretty much changed the landscape of the Batman mythos forever afterward. She was originally a psychiatrist at Arkham Asylum who tried to make a name for herself by curing the Joker. However, she fell in love with him, broke him out, and started a life of crime together. And the rest, as they say, is history.
PC Principal in Stunning and Brave - South Park

While some might find South Park's humor to be raunchy and inappropriate, you have to give it credit for being able to adapt with the times. After Principal Victoria is sacked from her job at South Park Elementary, PC Principal (real name Peter Charles) is hired in her place, and his debut certainly makes an impact. He's the enforcer of political correctness and is so strict that he even beats Eric Cartman to the point where he has to be hospitalized.
Safe to say, his debut was a major game changer for the show. And who can forget his catchphrase? "You better watch your microaggressions, bro!" Classic.
Casey Jones in Meet Casey Jones - Teenage Mutant Ninja Turtles (2003)

Even though Casey made an appearance in the 1990s cartoon, he was in only a few episodes. The 2003 reboot, however, gave his character way more depth and he felt like an actual key character rather than a one-timer. In this episode, Raphael goes topside to vent some steam and sees a vigilante wearing a hockey mask and using sporting equipment to fight crime.
However, Raph doesn't approve of Casey's methods and it's not long before they get in a real jam. Ever since then, Casey has felt like a true regular along with April O'Neil, among others.
Rebecca Donaldson-Katsopolis in Tanner vs. Gibbler - Full House

Three grown men trying to raise three daughters can be tiresome and make for all kinds of mishaps. In the second season episode Tanner vs. Gibbler, we see Danny getting removed from the sportscaster position at a TV station and paired with Rebecca Donaldson on the morning show Wake Up, San Francisco. However, she would appear in more episodes later on and join the main cast as Jessie's wife, thus giving the girls the motherly figure that they desperately need.
Denzel Crocker in Transparents - The Fairly OddParents

The Newcomers

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Oliver Tyler in Welcome Aboard - The Brady Bunch

Yup, it's Cousin Oliver. He was introduced at the tail end of Season 5 in an effort to revitalize the show because the other children were growing up and losing that youthful je ne sais quoi that made the show enjoyable.
But it backfired tremendously, which led to the show's ultimate cancellation. Although his appearance in the show was very brief, it left enough of an impact to be known as the Cousin Oliver Syndrome, where sitcoms introduce a new character (usually a cute kid) in an attempt to keep the show going.
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Gustavo Fring in Mandala - Breaking Bad

Gustavo "Gus" Fring is a fictional character from the television series Breaking Bad, created by Vince Gilligan. He is portrayed as a major antagonist in the series. Fring also appears in the prequel series Better Call Saul, where more of his background is revealed.

The Contenders

Sid Chang in Friended with the Casagrandes - The Loud House
Pebbles Flintstone in The Blessed Event - The Flintstones

Even though The Flintstones was designed to be watched primarily by adults, it can be enjoyed by children from time to time. One key moment in Fred and Wilma's life is the birth of their one and only child, Pebbles.
Shortly after, Barney and Betty Rubble adopt a son named Bamm-Bamm, and the two share a tight bond from childhood until they get married. This episode shows how having children is always a game-changer.
Toph Bei Fong in The Blind Bandit - Avatar: The Last Airbender
Willow Park in I Was a Teenage Abomination - The Owl House
Bill Cipher in Dreamscaperers - Gravity Falls
Benedict Uno/Father in Operation: G.R.O.W.-U.P. - Codename: Kids Next Door
Marceline in Evicted! - Adventure Time
Sandy Cheeks in Tea at the Treedome - SpongeBob SquarePants

Sandra "Sandy" Cheeks is a fictional character in the Nickelodeon animated television series SpongeBob SquarePants.
Discord in The Return of Harmony - My Little Pony: Friendship Is Magic