The long-running Showtime drama “Dexter” ended Sunday night, and fans finally learned the fate of the world’s most beloved serial killer, Dexter Morgan. Many were less than thrilled.

While producers Scott Buck and Sara Colleton have already stepped forward to defend the direction of the finale, fans have also shared their own opinions on social media. Following the series finale Sunday night, viewers took to Twitter in droves to slam the conclusion, which (spoiler alert!) shows Dexter faking his own death, leaving his son Harrison with his serial-killer girlfriend Hannah McKay, and starting a new life as a tree logger. “Step 1: hunt down the writers of ‘Dexter.’ Step 2: break knee caps,” said Twitter user R.J. Jackson Monday. Similar sentiments were shared by other fans of the gore-infused series. "The ‘Dexter’ season 8 finale was f--king awful. That is all,” said OnlyMairi.

Besides the overwhelmingly negative commenters on Twitter, other fans have taken to Showtime’s official Facebook page to gripe. “Showtime, why the ending? You totally messed up the Dexter series!!!” said Martina Vakatzas of Sofia, Bulgaria, Monday. A Phoenix-based fan, Adam Ceton, even accused the network of keeping Dexter alive in hopes of financially benefiting from a possible spinoff. “So frustrated at #Dexter. Really? That is how it ended?” he said, adding, “I knew going in there was now way to wrap it in one episode, but that was a huge letdown. The ending was so so so bad…Shame on you Showtime #diditforthemoney."

There is no denying that the season finale of “Dexter” has upset a majority of its fanbase, but the drama isn’t the only long-standing series to leave viewers wanting more. Here are four other series with controversial endings:

“The Secret Life of the American Teenager”

The ABC Family series “The Secret Life of the American Teenager” followed characters Amy Juergens (Shailene Woodley) and Ricky Underwood (Daren Kagosoff) from the conception of son John as teenagers, up until days before their wedding as twentysomethings. Despite the final seasons of the popular scripted show focusing on a future for the young parents, the series finale in June rocked fans' worlds after the couple shockingly decided to lead separate lives and call off their impending nuptials at the end of the episode, "Thank You and Good Bye."

Following the finale, show creator Brenda Hampton was flammed by viewers, with some fans even creating an online petition to get her to rewrite the series finale. "After watching the series finale, MILLIONS of fans are highly disappointed, and just plain pissed off! It was like a slap in the face for us viewers, and we feel robbed of the last five years of our live," said the Change.org petition, which received more than 1,300 signatures during its prime. "So ABC Family, and Brenda Hampton, are you planning on just letting your fans down, or are you going to do the right thing and correct this finale?" said the petition.

“The Sopranos”

A lack of an ending was what sparked outrage from fans following the series finale of the hit HBO mob drama, “The Sopranos.” The final scene, which showed the entire Soprano family enjoying a dinner at their favorite diner before cutting off suddenly before we learn the fate of the main character, mob boss Tony Soprano (played by the late James Gandolfini), all while a mysterious man can be seen watching over the career criminal.

After the backlash over the season six episode “Made in America,” the show’s supervising producer, Matt Weiner, stepped forward to confirm the show's lead character was scheduled to die two years before the finale aired in 2007. “There was only three possible scenarios for the ending: Tony gets arrested, Tony gets killed, Tony gets off,” he said during an interview with the Archive of American Television in 2010 on behalf of the show’s executive producer, David Chase. “If it wasn’t for the trick of it, it was a beautiful ending. To me, it’s always like smashing a guitar. Tony Soprano has left the building,” he later added.

“The Hills”

MTV’s “The Hills,” which followed a group of twentysomethings dating, hooking up, fighting and -- let’s face it— gossiping, was a huge hit for the network. Following in the footsteps of (and even stealing stars from) the now-defunct series “Laguna Beach,” "The Hills" shocked viewers after producers revealed just how fake the reality show was. Or is it?

In the July 2010 series finale, titled “All Good Things...," the show's season-six leads, Kristin Cavallari (a replacement for the series' original star Lauren Conrad) and Brody Jenner (you may recognize him from “Keeping Up With the Kardashians”), say goodbye after ending their on-again, off-again relationship. After the former couple part ways following a teary goodbye, a backdrop moves aside to show the entire scene was not shot behind the real Hollywood sign but on a movie set. Following the finale, multiple stars of the long-running series stepped forward to confirm the show was staged and highly edited.