There have been plenty of TV shows that astound viewers with an TV show based on a book was forced to move past its source material in later seasons.

While many great anthology shows that got everything right in their debut season, yet when it was time to shake things up with a new cast of characters for season 2, the show just didn’t feel as exciting. While not all of these shows were terrible in their later seasons, their legacy would have been far stronger had they called it a day after just one installment.

10 Altered Carbon (2018 - 2020)

2 Seasons

The first season of the Netflix cyberpunk series Altered Carbon was a boundary-breaking success based on the original novel by Richard K. Morgan. Set in a world where consciousness can be transferred to different bodies, this unique series explored the relationship between humans and machinery, gender identity, artificial intelligence, and paranoia. With elements of a murder mystery, the first season of Altered Carbon felt like it got everything right as it blended film noir, thrillers, and sci-fi stylings into a cohesive whole.

Sadly, Altered Carbon's second season was such a letdown that it made viewers wish it had just been a one-off miniseries. As a less clever and disappointing follow-up season, viewership declined, and Netflix canceled the show. However, Altered Carbon did return once more for an anime prequel spin-off set 283 years before the original show titled Altered Carbon: Resleeved, which received praise for its animation style but was highly criticized for its lackluster plot and disappointing characterization.

9 Riverdale (2017 - 2023)

7 Seasons

When Riverdale premiered in 2017, it appeared to be a genuinely exciting teen drama whose self-aware reimagining of Archie Comics made for a compelling, postmodern television viewing experience. With an intriguing premise, Riverdale felt like Twin Peaks for Generation Z as it kicked off with a murder mystery and hinted at the dark underbelly of a seemingly wholesome society. Riverdale had real potential to carve out something interesting, and if things had ended after season 1, it would have gone down as one of the most fascinating teen dramas ever made.

Unfortunately, Riverdale was continually renewed with diminishing returns every subsequent season. The sprawling melodrama of Riverdale grew increasingly unwieldy as it tackled the supernatural, social and political issues, and even time travel. While all these ideas have merit, the bloated 20-plus episodes of later seasons meant the show began to feel like it valued quantity over quality. Although Riverdale’s ability to reinvent itself continuously was irable, it begged the question of whether it would have been better to have left viewers wanting more.

8 Westworld (2016 - 2022)

4 Seasons

The first season of Westworld was an immensely satisfying dystopian sci-fi series based on Michael Crichton’s 1973 movie of the same name. As a clever, satirical HBO drama that explored artificial intelligence, technology, and humanity’s need for increasingly outrageous entertainment, Westworld packed all these aspects together into a fascinating mystery just waiting to be unpacked. With a twist ending involving multiple connected timelines, Westworld season 1 was a complete viewing experience with a satisfying conclusion.

While Westworld season 1 was such a success that many predicted it as the next Game of Thrones, all the goodwill it had built up was lost in the subsequent seasons. The sad truth was that Westworld became too clever for its own good and lost viewers in the process as the subsequent seasons became increasingly difficult to follow. Westworld also strayed further away from its futuristic Western theme park premise in its later seasons, which did it a disservice.

7 Killing Eve (2018 - 2022)

4 Seasons

The first season of Killing Eve was an incredible mix of strong characterization and sexual tension packaged in a thrilling spy series. With Fleabag creator and star Phoebe Waller-Bridge as the showrunner, the debut of Killing Eve had viewers on the edge of their seats while also keeping them amused with sharp, clever dialogue and powerful feminist themes. The sociopathic assassin Villanelle (Jodie Comer) was unlike any other killer on television, and the cat-and-mouse game between herself and the MI5 agent Eve Polastri (Sandra Oh) was a unique dynamic.

While Killing Eve had the potential to continue on this trajectory for more seasons, as it was based on a series of novels by Luke Jennings, Waller-Bridge exited the show after the first season, and her absence was sorely felt. Killing Eve’s later seasons attempted to recreate the magic of its debut run but never quite managed to reach the same heights. While it was never a bad show by any stretch of the imagination, it’s hard not to wonder if it would have been better as one perfect miniseries.

6 Your Honor (2020 - 2023)

2 Seasons

In its first season, Your Honor was a fantastic legal thriller that gave Bryan Cranston perhaps his greatest post-Breaking Bad role and made for truly nail-biting viewing. Following the story of Judge Michael Desiato’s misguided attempt to protect his son after he was involved in a hit-and-run, this unfortunate incident saw the pair wrapped up in an intense conspiracy involving New Orleans's most dangerous crime family. With great performances and an intriguing premise, Your Honor hit all the right notes as it powerfully explored how, given the right circumstances, good people can find themselves doing bad things.

The problem with the second season of Your Honor was that it just felt unnecessary and like a misguided attempt to extend the series needlessly. Despite Cranston's fantastic performance, there was no need to return to the story of Judge Desiato, as the show began with him bearded and disheveled in his prison cell. With a far less compelling story to tell this time around, Your Honor season 2 just did not have the same impact as the first.

5 True Detective (2014 - Present)

4 Seasons

When True Detective premiered in 2014, it felt like a total revelation as Woody Harrelson and Matthew McConaughey pulled viewers in with an intriguing mystery taking place over several timelines. The sheer star power on display was an impressive example of movie stars' willingness to move over to television for the right project during the 2010s. This also felt like an exciting continuation of the media-dubbed McConaissance, as McConaughey gave one of the most astounding performances in his entire career as the troubled detective Rust Cohle.

Having laid the foundations of a potentially masterful TV show, it was thrilling to hear that True Detective had been renewed for a second season. However, the show returned with an entirely new set of characters and continued as an anthology series focusing on a new mystery in each installment. Unfortunately, the second season starring Colin Farrell, Vince Vaughn, and Rachel McAdams just did not hit as hard and left many wondering if it would have been better if True Detective had continued with Harrelson and McConaughey at the helm.

4 Euphoria (2019 - Present)

2 Seasons

The HBO teen drama Euphoria felt like a million miles away from the lighthearted stories of Gilmore Girls or One Tree Hill from so many years before. Instead, this was a gritty tale of addiction, depression, and loneliness that struck a chord with modern audiences as young people related to the dark topics around hookup culture, codependency, and toxic masculinity. While Euphoria solidified the star status of actors like Zendaya and Sydney Sweeney, the second season did not have nearly as much cultural relevance as the first.

With a long-gestating third season of Euphoria in the works, the lackluster response to season 2 makes it seem like it might be better to let the cast move on to other projects. Both Zendaya and Sweeney have become far more famous and acclaimed in the years since Euphoria first premiered, and as two of the biggest movie stars on the planet, it feels like they have outgrown the show. Maybe Euphoria will recapture the dark appeal of its debut in season 3, but it would have become a modern classic if things had ended after just one season.

3 Glee (2009 - 2015)

6 Seasons

The opening episodes of Glee’s first season made for truly captivating television as its ensemble cast of theatrical high schoolers and its unique renditions of popular songs made it stand out. As an enjoyable satire of the high school experience that addressed social issues around sexuality, gender, race, and family head-on, Glee was both clever and fun to watch. This jukebox musical kept up its quality throughout the first season as the adult characters, like the teacher, Mr. Schuester, or the cheerleading coach, Sue Sylvester, added to the show’s humorous appeal.

However, the premise had already worn thin by the end of season 1, and as the show continued for five subsequent seasons, it felt like it became increasingly convoluted and ridiculous. What initially felt creative and fresh soon turned formulaic and stale as Glee moved away from its core cast and focused more on celebrity guests and gimmicky episodes. While Glee’s debut season felt like essentially viewing, most viewers had already moved on by the time it finally concluded.

2 13 Reasons Why (2017 - 2020)

4 Seasons

13 Reasons Why was a show whose premise was built into its title, and as an adaptation of a novel by Jay Asher, it truly should have had only one season. As the story of the aftermath of teen suicide and the deceased student who left behind a cassette tape detailing those she deemed were responsible, 13 Reasons Why touched on many important issues affecting young people today. With themes around bullying, depression, and self-harm, the first season of 13 Reasons Why was a well-written and highly accomplished examination of teenage grief and suffering.

Had 13 Reasons Why concluded after just one season, it would have been one of Netflix’s most impressive shows instead of a prime example of how things go wrong when TV series are needlessly continued. As season 2 moved past its source material, 13 Reasons Why lost sight of what made it compelling in the first place and devolved into increasingly convoluted plotlines. By the time the show ended after season 4, it was receiving overwhelmingly negative reviews, and its triggering topics had lost the nuance and poignant relevance of its earliest season.

1 Heroes (2006 - 2010)

4 Seasons

Set in a world where ordinary people discover that they possess superpowers, Heroes debuted two years before the start of the Marvel Cinematic Universe and was truly one of the most exciting shows on television at the time. With an incredible first season arc based around the catchphrase “Save the cheerleader, save the world,” Heroes boasted an incredible ensemble cast complete with characters of different abilities such as bending space and time, healing, or even mind reading. Heroes had the potential to be truly great in its later seasons, yet behind-the-scenes circumstances meant it should have ended at just one.

Heroes was a victim of the 2007 to 2008 WGA writers' strike, which meant that only 11 out of its planned 24-episode second season were made. These changes forced the writers and producers to restructure the season, and the show had a major decline in quality as a result. Despite being one of the most creative TV shows of the 2000s, Heroes was a victim of bad timing, and although there have been attempts to revive it, such as the short-lived sequel series Heroes: Reborn, it never again reached the astounding heights of season 1.