1. Firefly

When it went off the air: Canceled in 2002, just three months after the first episode aired.
Why it was canceled: When Fox pulled the plug, it was ranked 125th in the Nielsen ratings and averaged 4.48 million viewers. So, yeah, the ratings blew, but it remains a cult classic.
Potential for revival, on a scale of 1-10: 8, but not as a TV show. Serenity was a film spinoff of the series, and creator Joss Whedon has alluded to the idea that there may be another installment coming. Ya know, after he’s done with a zillion other things.

2. Dead Like Me

When it went off the air: In 2004, after two seasons.
Why it was canceled: Creator Bryan Fuller, who left after five episodes into Season 1, stated that the show was terminated because of “a loss of quality and a sense the problems would continue.”
Potential it could be revived, on a scale of 1-10: -5. Aside from the fact that it sounded like a poor work environment on set, Mandy Patinkin is currently booked on Homeland, and a film version of the show was released in 2009. It’s dead… like me, after realizing it won’t ever come back.

3. Freaks and Geeks

When it went off the air: In 2000 on NBC, after airing only twelve episodes of the eighteen episode order. A fan campaign persuaded NBC to air three additional episodes, and the series was aired in full on Fox Family during syndication.
Why it was canceled: Freaks and Geeks was ranked 93rd in the ratings race. Hey, it’s better than 94th… right?
Potential it could be revived, on a scale of 1-10: 0. The unofficial spinoff was a show called Undeclared, which centered around college freshmen, and was also canceled after one season. But they did have a photoshoot reunion in 2012, if that’s any consolation.

4. Pushing Daisies

When it went off the air: The last episode aired in December of 2008.
Why it was canceled: After the writers strike in 2008, Pushing Daisies came back and wasn’t able to pick up steam in the ratings race. In spite of its 12 Emmy Award nominations, it wasn’t picked up for a third season.
Potential that it could be revived: 10, because creator Bryan Fuller has admitted to working on a film version, and talked about taking his film to Kickstarter. (Come on, Pushing Daisies fans!)

5. Everwood

When it went off the air: In 2006, after four seasons.
Why it was canceled: In spite of ratings that were fine by CW standards, Everwood was canceled and replaced by a new show called Runaway. That replacement show was then canceled after three episodes, and the slot was given to an eleventh season of 7th Heaven.
Potential that it could be revived: 0, and some have described the possibility of a revival as, “The show is dead. Buried. Gone for good.”

6. Kyle XY

When it went off the air: 2009
Why it was canceled: After three seasons, it was rumored that the series ended with a lot of unresolved story lines because of poor ratings.
Potential that it could be revived: 1. Seeing as showrunner Julie Plec included a “wrap up” in the Season 3 DVD, which included what would have happened in the series. Plec also has roughly one million* other shows currently on the air.

(*My own exaggeration.)

7. Las Vegas

When it went off the air: The series ended on an abrupt cliffhanger in 2008, after five seasons.
Why it was canceled: It was noted as a victim of the writers strike, with costs being too high afterward to renew.
Potential it could be revived: 0, seeing as James Caan and Nikki Cox left the series in the fourth season, and there have been no rumors of revival.

8. Moonlight

When it went off the air: In 2008, after a 16 episode season.
Why it was canceled: Vampire shows are totally hot right now, but when the show aired in late 2007, it didn’t hit well with critics or ratings.
Potential that it could be revived: 2. When the series was initially canceled, writer and EP, Harry Werksman, tried to sell a second season to another network, and even discussed the possibility of a film. None of those plans have panned out… yet.

9. Jericho

When it went off the air: In 2008, after two seasons.
Why it was canceled: The show was actually canceled twice. The first time came after the first season aired. It was renewed for a second season, thanks to an impressive fan campaign effort. Then promptly canceled again.
Potential that it could be revived: 5, as there have been talks of a feature film since 2009.

10. Roswell

When it went off the air: 2002
Why it was canceled: The show’s first two seasons aired on the WB, and suffered in the second season after the show shifted to include more sci-fi themes. The third and final season aired on UPN, immediately after Buffy, but couldn’t hold on when it came to the ratings game.
Potential that it could be revived: 0, especially when you consider that even the book series was canceled.

11. Twin Peaks

When it went off the air: 1991
Why it was canceled: Ratings declined significantly in season two, after Laura Palmer’s murder was resolved, and continued to go down with several time slot changes.
Potential that it could be revived: 0. A film version called Twin Peaks: Fire Walk with Me came out in 1992, and since then creator David Lynch has stated that he has no interest in continuing the series.

12. Deadwood

When it went off the air: In 2006 after three seasons.
Why it was canceled: It’s a little unclear as to why the show was left on such a cliffhanger. It could be that it had a very specific audience that just wasn’t driving enough ratings to justify the cost of a period piece show. But the specific reason has always been a bit murky.
Potential that it could be revived: 2, creator David Milch has said that the possibility is highly unlikely, as they’ve come close to film versions, but it has yet to happen. Again, there’s that word “yet.”

13. My So Called Life

When it went off the air: 1995
Why it was canceled: Claire Danes played a big role in the show’s cancelation, as she approached producers and said that she didn’t want to be part of a second season. Couple that with not stellar ratings, and the show was off the air after just one season.
Potential that it could be revived: Aside from re-runs … negative a million and one.

14. Ugly Betty

When it went off the air: In 2010, after four seasons.
Why it was canceled: Between the third and fourth seasons of Ugly Betty, the show dropped from 8.1 million viewers to 5.3.
Potential that it could be revived: 5, as star America Ferrera has said, “It’s so wonderful that the fans care so much that this question about the movie just keeps coming up. It’s not anything that’s actually in the works but is something that’s always a possibility, and it’s wonderful to know that the fans want it.”

15. Happy Endings

When it went off the air: In early May of 2013, after three seasons.
Why it was canceled: The usual suspect’s behind this one: low ratings. But Rolling Stone called it, “the most underrated, under-watched series on the air today.” Not that it will make you feel any better, but hey—better than nothing!
Potential that it could be revived: 8. The show is currently being shopped to other networks, though has yet to find a home. So, if you’re a fan, now’s the time to start a movement!

16. Enlightened

When it went off the air: It was canceled this past March, after two seasons.
Why it was canceled: Low ratings.
Potential that it could be revived: 2. Nothing’s impossible, but even a Twitter/Tumblr campaign by the fans couldn’t save the show. Creator Mike White did detail what a third season would’ve included, if you want to know the ending.

17. Dollhouse

When it went off the air: In 2010, after two seasons.
Why it was canceled: It was only the power of Joss Whedon’s fan base that even gave the show a second season. With one Fox exec stating, “If we’d canceled Joss’s show I’d probably have 110 million e-mails this morning from the fans.” After that, it was canceled due to poor ratings.
Potential that it could be revived: 0. If only because I’d selfishly want to see a Firefly reboot first.

18. Heroes

When it went off the air: 2010, after a four season stint.
Why it was canceled: Ratings strikes again, as the fourth season premiere was the lowest rated episode in the series up to that point, bringing in 5.9 million viewers.
Potential that it could be revived: 9, as it’s rumored that MSN may revive the series in conjunction with plans for original Xbox programming.
Fun Fact: Bryan Fuller had a brief stint writing on Heroes, after Pushing Daisies was canceled.

19. Party Down

When it went off the air: In 2010, after two amazing seasons.
Why it was canceled: Losing Jane Lynch to Glee and Adam Scott to Parks and Recreation didn’t help the already low ratings.
Potential that it could be revived: No revival has been discussed, though the cast did “reunite” on Twitter in 2013, and in costume, no less!

20. Smash

When it went off the air: Canceled in 2013, with the series finale airing this Sunday, May 26.
Why it was canceled: Ratings is officially to blame, but BuzzFeed’s own Kate Aurthur may have foreshadowed what was to come in her piece, “How “Smash” Became TV’s Biggest Train Wreck.”
Potential it could be revived: There’s been no murmurs of any promise yet, but that may be just because the show is still on the air.

16. Forcing Jesse to cook meth by threatening to turn him in otherwise.

Episode: “Pilot” (Season 1, Episode 1)
This is how it all begins — “You know the business, I know chemistry.” But Jesse doesn’t partner up with Walt willingly, at least not at first. It’s only after Walt threatens to turn Jesse in to Hank that his former student agrees to cook with him. The only mitigating factor here is Walt’s desperation: He’s just gotten his cancer diagnosis, and he knows he needs to come up with fast cash.

15. Pressuring the laundromat employees to clean his lab and getting them deported.

Episode: “Cornered” (Season 4, Episode 6)
Walt’s entitlement knows no bounds, as when he goes against Gus’s wishes by enlisting laundromat employees to clean the lab. He sits back and watches them work, even raising his cup to the surveillance camera, oblivious to the fact that he is sealing their fate. The women are eventually sent back to Honduras, which Walt at least acknowledges is entirely his fault.

14. Refusing to leave Skyler alone.

Episode: “I.F.T.” (Season 3, Episode 3)
“It’s my house, too, Skyler, and I’m staying.” Walt’s stubborn insistence on invading Skyler’s space continues throughout the series. Once Skyler learns the truth about Walt’s business, she makes it clear she doesn’t feel safe around him — but that only makes him assert his dominance more. When Skyler later calls herself Walt’s hostage, she’s not far off.

13. Kicking Jesse out of the business.

Episode: “Más” (Season 3, Episode 5)
As awful as Walt is to Skyler, his treatment of Jesse is consistently reprehensible, based entirely on how much he needs him at any given moment. When Walt is working for Gus and no longer needs Jesse as a partner, he snaps, “That is the last money you’ll ever earn in this business. I’m in, you’re out.” It’s a brutal send-off to someone who considered him a friend.

12. Turning Jesse away when he had nowhere else to go.

Episode: “Down” (Season 2, Episode 4)
Or how about when Jesse was broke and homeless and turned to Walt for help? Sure, Walt has his family to think about, but he’s still unusually cruel to the “pathetic junkie.” “Your problems are just that,” Walt tells Jesse. “Your problems.” By the end of the episode, the two are working together again — but that’s, of course, when Walt wants to cook again.

11. Ratting Jesse out to Saul and trying to have him arrested.

Episode: “Half Measures” (Season 3, Episode 12)
Walt may think he’s protecting Jesse when he tries to stop Jesse from poisoning dangerous drug dealers — but he’s putting Jesse’s life in serious danger. When Walt rats Jesse out to Saul, suggesting there might be a way to get Jesse arrested, he’s also ratting his partner out to Gus and Mike. They could have easily taken Jesse out to prevent a turf war.

10. Driving Hank and his car into traffic.

Episode: “Crawl Space” (Season 4, Episode 11)
Walt will do anything to prevent Hank from finding out the truth about his secret life, even if that means nearly killing them both in an accident. But it’s the careless disregard for Hank’s life that’s really shocking, especially given how much Hank has already suffered in pursuit of Heisenberg. Remember, this is a man who just learned how to walk again.

9. Locking Emilio and Krazy 8 in the RV with poison gas.

Episode: “Pilot” (Season 1, Episode 1)
Again, this is a product of Walt’s desperation, and it’s basically self-defense. At the same time, it’s the first instance of our “hero” taking someone else’s life. (He intends to kill both men, but Krazy 8 survives. At least initially — see below for his ultimate fate.) Walt’s murder of Emilio, however necessary, sets a dangerous precedent for his drug business.

8. Strangling Krazy 8.

Episode: “…And the Bag’s in the River” (Season 1, Episode 3)
After nearly killing Krazy 8 in the pilot, Walt finishes the job in the third episode. It’s still self-defense — and even more pressing, as Krazy 8 is trying to stab him with a shard of broken plate — but it’s horrific. And unlike the more passive homicide by poison gas, it requires Walt to really get his hands dirty as he squeezes the life out of his victim.

7. Running over and shooting the drug dealers.

Episode: “Half Measures” (Season 3, Episode 12)
On the one hand, he’s saving Jesse’s life. On the other hand, he’s killing two people in cold blood. The brutal conclusion of “Half Measures” is a major turning point for Walt, who takes on a much more active and aggressive role in his business. Running the men over is shocking, but shooting one in the head leaves the audience speechless.

6. Killing Gus with a bomb at a nursing home.

Episode: “Face Off” (Season 4, Episode 13)
Gus had to go. But did he have to die at the risk of injuring a bunch of elderly people at a nursing home? Relax, the innocent people escaped unscathed. And yet, it takes a truly single-minded individual to put so many bystanders in danger just to get rid of one man. Walt’s plan to kill Gus is satisfying for the audience, but it speaks to his utter lack of morality.

5. Ordering the murders of nine inmates and Mike’s lawyer.

Episode: “Gliding Over All” (Season 5, Episode 8)
In a montage reminiscent of The Godfather, Michael Corleone — er, Walter White — cements his role as drug lord by ordering the murders of nine prison inmates and Mike’s lawyer in order to protect his empire. They’re all criminals, but that doesn’t justify their awful deaths. Nor does it vindicate Walt, who can only do this because he’s already killed Mike. (See below.)

4. Shooting Mike.

Episode: “Say My Name” (Season 5, Episode 7)
And we’ve finally reached the point where Walt kills not because he has to but because he feels like it. Shooting Mike is pure ego, a decision he makes out of anger over Mike’s supposed disrespect. Mike himself was not a good guy, but he had his own code of honor, which makes Walt murdering him all the more shameful. (Mike is also, it’s worth noting, a fan favorite.)

3. Making Jesse kill Gale.

Episode: “Full Measure” (Season 3, Episode 13)
One of the worst murders Walt commits isn’t done by his own hand. But forcing Jesse to become a killer — something Jesse had avoided up to that point — destroys two lives. Even if Walt believes he has no other choice, there’s no excusing the murder of Gale, a true innocent, and the unbearable burden it places on Jesse’s conscience.

2. Letting Jane choke to death on her own vomit.

Episode: “Phoenix” (Season 2, Episode 12)
Walt may not have intended for Jane to die, but he had ample opportunity to save her. Instead, he makes a conscious choice, perhaps believing he is doing the right thing. And yet, Jane’s death carries tremendous consequences, sending Jesse further into addiction, and ultimately causing the collision of two planes and the deaths of their passengers. All because Walt wouldn’t turn her on her side.

1. Poisoning Brock.

Episodes: “End Times” and “Face Off” (Season 4, Episodes 12-13)
It’s hard to imagine a lower point for Walt than when he poisons a little boy. Brock is not an enemy but merely a pawn to get Jesse back on Walt’s side in the war against Gus. Walt’s righteous indignation when accused of the crime only makes things worse: By this point, he has fully crossed over to the dark side, where poisoning an innocent child is a necessary evil.