Buzz
Introducing new characters to a long-running show isn’t always an easy feat. There's actually a term for it – the 'Cousin Oliver' trope, inspired by the character from the 1970s sitcom The Brady Bunch. This list dives into TV characters introduced later to 'shake things up.' While this trope often has a negative reputation, not all late additions receive backlash from fans. For every Scrappy-Doo, there's a standout who wins over audiences and critics alike.
Let's take a look at ten beloved TV characters who weren't part of the original cast. However, be warned—there are some spoilers ahead.
10. Frank Reynolds: It’s Always Sunny in Philadelphia
The hit FX series It’s Always Sunny in Philadelphia has become one of the longest-running comedies on TV. As of 2022, the show boasts 15 seasons and continues to thrive. From its modest origins, it’s fair to call it the underdog that made it big. In the early 2000s, Charlie Day, Glenn Howerton, and Rob McElhenney, aspiring actors at the time, crossed paths while auditioning for other roles. They eventually began shooting their own home movies on a Panasonic DVX100A, leading to the creation of It’s Always Sunny.
After filming a pilot on a camcorder, the show was picked up by the cable network FX. While it initially struggled to find an audience, the executives at FX had faith in its potential. They eventually realized the cast was missing something and decided to bring in a major name.
Enter Danny DeVito.
Although the cast initially had reservations, DeVito joined in season 2 as Frank Reynolds, Dennis and Dee’s stepfather. The character is a stark contrast to the warm, lovable roles DeVito is usually known for. Instead, Frank is crude, vulgar, and cynical, which made him the perfect fit for the show’s dark humor. His addition revitalized the series, pulling it away from the brink of cancellation. Many long-time fans agree that DeVito's portrayal of Frank was the key element that turned a good show into something great.
9. Ben Linus: Lost
For fans of the popular ABC series Lost, it’s hard to imagine that Benjamin Linus wasn’t originally part of the cast. The mystery-laden drama captivated audiences from the start. While the first season was already a hit, the show’s popularity only increased with its second season. Much of this success can be credited to the introduction of Michael Emerson, who played the enigmatic Ben.
For most of season 2, Ben was imprisoned and tricked the main group into believing he was a man named Henry Gale. When his deception is exposed at the end of the season, it’s revealed that Ben is actually the leader of The Others, a mysterious group living on the uncharted side of the island. Even worse, Ben had been exactly where he wanted to be for most of season 2—watching the group. Ben’s morally ambiguous nature, hunger for power, and occasional violent tendencies are just a few reasons why he's become a fan favorite.
8. Fin Tutuola: Law & Order: Special Victims Unit
Similar to Danny DeVito’s role in It’s Always Sunny in Philadelphia, Ice-T was already a well-known figure in the entertainment world before joining Law & Order: Special Victims Unit in its second season. He portrays Odafin 'Fin' Tutuola, a tough, street-smart cop who transfers from the narcotics division to the SVU. Fin has a rough exterior, but a deep passion for helping victims of abuse, assault, and child exploitation. Initially paired with the cynical, conspiracy-loving detective Munch, Fin’s relationship with him was a fan favorite, and many felt their dynamic was as strong as that of the show’s main characters, Benson and Stabler.
Fin has remained a core member of SVU for over 22 years, making him the longest-serving non-original cast member on this list. After Elliot Stabler's departure from the squad in 2011, Fin became Captain Benson's trusted right-hand man and her longest-running supporter.
7. Rafael Barba: Law & Order: Special Victims Unit
The assistant district attorney role on Law & Order: Special Victims Unit has seen many faces over the years. While Alexandra Cabot and Casey Novak have earned their place in fans' hearts, Rafael Barba managed to carve out a name for himself and became a serious contender for their popularity.
Barba, portrayed by Broadway star Raul Esparza, made his debut in the season 14 episode 'Twenty-Five Acts,' marking him as the most recent character to join the show on this list. His performance was so well received that he was promoted to a series regular the very next season. Known for his sharp mind and impeccable style, Barba's no-nonsense approach and sharp three-piece suits won over fans. He was also the first male assistant district attorney to be part of the main cast.
In 2018, Esparza chose to leave SVU to return to his stage career. His character’s departure in the episode 'The Undiscovered Country' was met with mixed reactions, but since then, Barba has made several guest appearances in seasons 21 through 23.
6. Desmond Hume: Lost
Desmond Hume is one of the most mysterious and compelling characters from Lost, which is no small feat considering the show's overall complexity. His unforgettable first appearance, locked inside the hatch, became one of the series' most iconic moments. Though he only appeared briefly at the start of season 2, his character’s storyline grew, and Desmond eventually became a regular cast member in the following season.
At first, Desmond appears to have lost his mind, which isn't surprising considering his years of isolation, convinced the outside world had ceased to exist. As the series unfolds, we learn more about his past, including a beautiful love story with his wife, Penelope. Desmond takes center stage in the beloved season 4 episode 'The Constant,' which, according to fans on IMDb, is tied with 'Through the Looking Glass' as the highest-rated episode of the series. Desmond's journey stands apart from most characters on Lost, and it's this uniqueness, along with his warm and compassionate nature, that makes him a fan favorite.
5. Tommy Oliver aka the Green/White Ranger: Power Rangers
The first season of Mighty Morphin Power Rangers became an unexpected hit with millennials in the mid-1990s. Kids couldn’t get enough of these five color-coded, karate-kicking superheroes. But the show took a dramatic turn when, in the 17th episode of the season, it introduced an evil ranger. Tommy Oliver, the new kid in town, was also under the control of Rita Repulsa, the villains' leader.
What made Tommy a fan favorite wasn’t just his long hair and rebellious demeanor—audiences also connected with his personal journey of seeking family and acceptance. The writers crafted a standout redemption arc where Tommy eventually frees himself from Rita’s spell, and ultimately leads the team as the White Ranger. Tommy’s relationship with Kimberly, the Pink Ranger, also became one of the show’s iconic romances.
4. Michonne: The Walking Dead
Michonne Hawthorne is one of the most iconic and deadly characters from the hit AMC series The Walking Dead. While she's a fan favorite, many long-time viewers forget that Michonne wasn’t part of the original cast—although she did make a brief appearance as a mysterious cloaked figure at the end of season 2. She wouldn’t join the regular cast until the following season.
At first, Michonne journeys alongside Andrea, a central character during the first two seasons. However, the two soon go their separate ways when Andrea decides to stay in the enigmatic community of Woodbury, a place Michonne instinctively distrusts. She sets off alone and, by chance, encounters Rick Grimes and his group, which originally included Andrea. Though initially skeptical, Michonne bonds with Rick’s son Carl and eventually enters into a romantic relationship with Rick.
Michonne, portrayed by Black Panther star Danai Gurira, remained a central character on The Walking Dead until season 10. Her on-screen kills are believed to rival those of Rick Grimes and Daryl Dixon in terms of sheer volume and impact.
3. Klaus Michaelson: The Vampire Diaries
Completing the list is yet another vampire—well, hybrid to be precise. The Vampire Diaries quickly became a teen TV sensation when it debuted in 2009. Although the show had a strong start in its first season, it truly kicked into high gear in season two, which introduced the Originals, a powerful family of vampires, and centered the plot around them.
Klaus stands as the patriarch of the Originals, the first vampire family in TVD lore, setting him apart from ordinary vampires. Unlike most vampires in The Vampire Diaries universe, who can be killed with any wooden stake, the Originals can only be slain by a stake crafted from the wood of an ancient tree. Klaus also possesses werewolf traits, making him the first hybrid in this cinematic universe.
Klaus's impact extends beyond just his supernatural strength and power. Played by the remarkably talented Joseph Morgan, often regarded as one of the CW's finest actors, Klaus is not only a dominant alpha but also a deeply conflicted soul. His character's emotional depth and fierce loyalty to his family made him so beloved that he was given his own spinoff series, aptly named The Originals.
3. Spike: Buffy the Vampire Slayer
Buffy the Vampire Slayer is widely regarded as one of the most impactful and critically acclaimed supernatural teen dramas ever to hit television. Initially conceived by writer and director Joss Whedon as a reimagined version of the 1992 film, the show quickly became a cultural phenomenon.
In the second season’s third episode, Buffy the Vampire Slayer introduced the character of Spike, a charming, bleach-blond vampire portrayed by James Marsters. Spike, with his leather jacket and motorcycle, exudes a rebellious, bad-boy charm. His character serves as the polar opposite to Angel, Buffy’s boyfriend and the only vampire with a soul. While Angel strives to live up to his name, Spike embraces his darker nature with relish.
Beneath his tough, rebellious exterior, Spike is a romantic who truly believes in the transformative power of love and poetry. His tumultuous and often divisive romance with Buffy remains a topic of passionate debate among fans, even years after the show ended. Not only did Spike play a major role in Buffy the Vampire Slayer, but he also became a central figure in its spinoff, Angel.
2. Lexa: The 100
Few characters have sparked as much controversy with their death as Lexa from The 100. A post-apocalyptic drama that aired on the CW from 2014 to 2020, the show followed 101 juvenile delinquents who were sent to Earth from a space station 97 years after humanity’s destruction. While it didn’t dominate the ratings, the series cultivated a loyal and passionate fanbase over its seven seasons.
In its second season, The 100 introduced one of its most memorable characters: Lexa, a fierce and strategic warrior queen, portrayed by Alycia Debnam-Carey. Lexa’s arrival mirrors that of Ben from Lost, with the audience initially mistaking her for a humble servant. However, it's soon revealed that she is the commanding leader of the Grounders, the main enemies (and later allies) during the first two seasons.
Lexa's love story with Clarke, the show's protagonist, quickly became one of the most significant relationships on The 100. In the third season, just after their romance reached its peak, Lexa was tragically shot by a stray bullet meant for Clarke. This devastating moment was compounded by the fact that Debnam-Carey had also secured a lead role in Fear the Walking Dead, which led to her inability to continue on The 100. Fans were outraged, sparking public backlash and a noticeable drop in both viewership and sponsorships, and though the series limped on for four more seasons, it never fully recovered its previous momentum.
