There are few things in life more disappointing than investing dozens of hours into a television show, only to watch said show devolve and mutate into something terrifically awful. This happens often on television, as many networks insist on keeping popular (and profitable) television shows on the air despite the fact that most of the creative staff have checked out and are simply there to continue collecting what (we can only assume) are life-altering amounts of cash. Most of the time, the moment where these TV shows transition from epic to awful is called “jumping the shark”, in reference to an episode of Happy Days where Fonzie quite literally jumped over a shark on water skis. Now a cultural idiom, jumping the shark speaks to a show’s ability to deteriorate in spectacular fashion; as such, we’ve collected 10 great television shows and highlighted when to stop watching them, so as to save you the heartbreak of seeing them water ski.

10. How I Met Your Mother

When to Stop Watching: Season 6

How I Met Your Mother, which aired on CBS for nine seasons, is a great show to kick this list off for a wide variety of reasons. Once consistently cited among the best sitcoms on television, How I Met Your Mother is a prime example of a show “jumping the shark.” Most fans agree that this happens somewhere around the beginning of season six, so we’re recommending you stop at the end of season 5 (which still features some absolutely hilarious episodes, including the one where Barney gives up wearing suits. Classic.). A television show with an overarching plot that should have ended three seasons sooner than it did, How I Met Your Mother was very clearly kept on the air as a money-making vehicle due to the show’s overwhelming popularity. Trust us on this one; it’s pretty obvious Neil Patrick Harris is the only cast member who bothered to try over the show’s final seasons. With a groan-worthy ending that most fans called years in advance, How I Met Your Mother is a great watch…if you stop at five.

9. Homeland

When to Stop Watching: Season 3

Homeland, which stars Claire Danes, Damien Lewis, Morena Baccarin and Mandy Patinkin, had an absolutely stellar first season. The show started as a gripping, well-acted political thriller that revolves around a recently released prisoner of war (Lewis) and the CIA officer (Danes) tasked with ensuring he isn’t a covert operative sent to wreak havoc on American soil. With one of the strongest pilots in recent memory and a solid first season to boot, you may be asking yourself “What went wrong with Homeland?”. We’re still asking ourselves the same thing. The show, which has devolved into a melodramatic yawn that’s impossible to take seriously, should be disregarded following the insanity of the season two finale. Do yourself a favor and skip season three and everything after. The first few seasons are great though, and definitely worth a watch for fans interested in espionage and the like.

8. Weeds

When to Stop Watching: Season 4

Weeds is the kind of show you want to love the whole way through, as it’s got a fairly lovable set of quirky characters and a premise interesting enough to carry a few seasons — a suburban housewife gets caught up in the drug trade after the death of her husband — relatively well.  That being said, the show changed so dramatically over the course of its tenure on Showtime that it probably should have been broken down and divided into Weeds and Weeds II: The Aftermath (Yeah, we know it’s bad. It’s a working title, alright?). Created by Jenji Kohan and starring Mary Louise Parker, Weeds is a perfect example of a show that started great before taking far too many sharp left-hand turns.

7. Entourage

When to Stop Watching: Season 5

Entourage is a great show to watch with your guy friends, and for the first four seasons, it’s a really great ride. Filled with girls, parties, the appeal of celebrity, and more cameos than you can shake a really big stick at, Entourage begins to get a little tired when the patented “Vince wants a movie role -> Vince can’t have the movie role -> Vince tries really hard and eventually gets movie role -> Movie is good/bad, it doesn’t really matter -> Vince is down, but don’t count him out! He has Ari and E helping him!” formula starts bordering on repetitive. We’re not joking when we say that that storyline makes up the bulk of every season; toss in a few quality rants from Ari Gold (played gleefully by Jeremy Piven), some incredibly attractive women wearing little clothing, and a fast car or two, and you’ve got Entourage in a nutshell. And for the first few seasons, this works really, really well. It’s wildly entertaining, in fact. But eventually, you start to yearn for the little things, like character development, plots, three-dimensional female characters, etc. And when you get to that point, all of a sudden Entourage isn’t all that much fun anymore.

6. The O.C.

When to Stop Watching: Season 3

Despite the fact that it’s taken a beating in the pop culture arena due to some occasionally wooden acting (we’re looking at you, Mischa Barton) and a good dose of melodrama (not that that’s always a bad thing, mind you), The O.C. actually had a few really solid seasons before heading off the deep end in season three. If you just stick to the first two seasons of the show, what you’re left with is a surprisingly solid cast (many a young heartthrob got their first gig here), an excellent soundtrack, and enough naturally generated drama to support a potential binging marathon. Again, just make sure you stop watching before that crazy surfer guys joins the cast, alright?

5. Prison Break

When to Stop Watching: Season 2

We can only imagine the atmosphere in the writer’s room when somebody, probably the showrunner or lead writer, took a look at how Prison Break’s first season ended and said out loud “…but what do we do for Season 2?”. Answering once and for all of our questions about how boring life really is after the prison break, Prison Break’s final three seasons never really touched the dramatic heights established in the first, and it’s really not difficult to figure out why: on a show called Prison Break, what are you supposed to talk about after they’ve broken out of prison? We’re still not sure how to answer that one.

4. Californication

When to Stop Watching: Season 5

It’s a real shame to watch the later seasons of Californication, since they really do spoil what had turned into a nice little show. While it took a while to transcend the jock humor that pervades its first few episodes, during its prime seasons, Californication was an entertaining, insightful, and surprisingly heartfelt endeavor that gave us our requisite David Duchovny fix and brought us out of our post X-Files haze. That’s all lost now, however; the later seasons have undone all the good wrought in Californication‘s earlier ones, with Duchovny’s Hank Moody no longer possessing the intelligence and underlying goodness that once defined the character. Now, the show acts simply as a vehicle for Moody’s philandering, drinking, and other incidents of bad behaviour. We’re not saying the good seasons didn’t have all that too, but at least then you got the impression Hank felt bad about it.

3. Heroes

When to Stop Watching: Season 2

Heroes is pretty much a crash course in how to mess up a promising television show. The show’s first season, with its quality plotline revolving around one menacing serial killer, and a “save the cheerleader, save the world” tagline that perfectly encapsulated the show’s oeuvre, is absolutely awesome; it did a great job navigating between multiple storylines, and the show’s super powered protagonists and antagonists actually looked really, really cool. The show didn’t suffer at all for having a television budget, but it did suffer mightily from its involvement in the 2007-2008 Writers Guild of America strike. The show’s second season was heavily impacted by the strike, and it’s an absolute disaster in comparison to what came before it. The show’s third and fourth seasons deliver more of the same, and with a reboot of the property — Heroes: Reborn — having premiered recently, we’re betting NBC is hoping that this version of Heroes has more in common with the stellar first season of Heroes and not the last three.

2. Lost

When to Stop Watching: Season 3

There’s not a whole lot we care to say about Lost that hasn’t already been said. We, like everyone else, were wildly addicted to the first two seasons, finding the show’s mysterious island and its seemingly endless chest of mysteries as engaging as anyone who was happy to consider themselves among the show’s legion of fans. Unfortunately, we were also increasingly frustrated by the show’s lack of answers and refusal to abide by its own mythology, and were very frustrated when the writers seemed to abandon five seasons of material in order to feed their audience some jumbled jargon and meaningless platitudes about good and evil. It all came across as an excuse to get out from under all the ridiculous storylines that hadn’t been answered. In the end, it was clear that the writers simply didn’t have the answers and Lost’s initial promise faded from memory as the credits for the extremely divisive finale started rolling.

1. Dexter

When to Stop Watching: Season 4

We too felt deceived when it was pointed out to us that each of Dexter’s seasons follow the same basic formula, patterned after the show’s incredibly successful first season; that said, we still enjoyed those shenanigans up until the show descended into some very strange territory, all of which began in season five. While it feels unfair to recommend that fans stop watching after season 4, considering that season ends on a massive cliffhanger and finished up an extremely tense season featuring an incredible performance from guest star Jon Lithgow as The Trinity Killer, who remains Dexter’s fiercest foe. While Dexter once held an esteemed position in the annals of television history, it went onto spoil that standing with shoddy writing and a total lack of character development…but it was a real fun ride while it lasted. We recommend everyone check out those first four seasons and forget about the rest.