I loved the first season of "Heroes" and thought it had such great potential. I watched and bought the 2^nd on DVD and couldn't even get through it again.

When 3^rd Season came around, of course i was gonna see what happened and it got slightly better, but i really have no interest in going any further with the series and might be content in just hearing what happens in passing or online for S4.

So what other shows were heralded upon release, gained momentum and then got derailed to the point of (almost) unwatchable or you simply lost interest all together?

Boom Town -- the original premise was to see a crime from various perspectives, but that was dropped after only a few episodes and it became a standard cop drama. It was still a good show, but not nearly as good as it had started.

Bones.

I still like the show, but last season was a mess. It was a hodge podge of bad comedy/jokes. And I think the rotating lab assistants and focusing on the personal relationships of Hodgins, Angela and Cam really bogged down the show. The season finale (the fantasy episode) was probably one of the worst episodes the series has ever concocted.

I hope next season goes back to being a crime procedural and focusing on the relationship between Booth and Bones.

I'll see your Heroes , and raise you Prison Break.

The first 2 seasons were fantastic, which shouldn't be too surprising considering that they initially conceived it as a 2-season arc. The subsequent seasons, while introducing a few characters of substance, really started to grate with me. I am glad that it was able to wrap the storyline, although they were really starting to stretch for a while.

Weeds. That is probably the biggest offender that I can think of.

Samantha Who is another show that lost its way, at least for me. The first season was great, but the second season really wasn't that great. Strayed too far from the subject matter and into generic sitcom plots with little to no focus on the amnesia aspect that made the show interesting in the first place.

Weeds came to mind first for me, too.

I agree about Heroes. Enjoyed the first season and couldn't last past the 4th episode in the second season.

Not sure if they lost their way or if they went on 2-3 more seasons than they should have (are they the same thing?):
The Practice - When it turned into The Kelli Williams Show, I tuned out.
The X-Files - This show should have ended when David Duchovny left the first time.

Heroes was the first to come to mind.

I'll also throw in Deadwood.

Sliders - Once the core group started breaking up, there was no point anymore.

Millennium - The 2nd season ruined the vision of the show

Prison Break - This was a two season show. period. There was the prison break and then they were fugitives. You can't go anywhere after that.

24 - Jack Bauer become too much of a superhero, They stayed in LA every season. And oh yeah once his family became the masterminds. 24 was done.

This remark was valid a year ago, but Season 7 was a big step up.

I disagree wholeheartedly.

I actually enjoyed season 4 a lot more than season 3. Havn't seen season 5 yet though.

I was going to say "Heroes" as well. Also "ER"... it was a great show but then it just kept getting worse and worse. I tried to watch an episode several years ago and just couldn't sit through it. The series finale was a hard one to watch as well and they had an original writer and most of the cast.

Apparently Chris Carter and the actors hated it. Carter was too busy with The X-Files and so he handed over the reigns thinking they would stick with his vision and they didn't.

But yes there seems to be a divided line of people who hated the 2nd season and people who think it improved upon the show. It's interesting.

Heroes, Life on Mars (US). Life on Mars was only one season, but the last episode was a huge drop from the previous one.

Also do not forget they didn't even know if the show would be renewed or not. I don't know about you guys but if I'm on a sinking ship it's hard to stay focused on the original plan.

My first thought getting back to the OP is Smallville. I liked the original concept of Clark maturing and growing into the super hero he would eventually become. But the freak of the week and the actress' that couldn't act if their life was dependent on it was the end for me. Oh, also the shitty scripts helped.

i thik Life on Mars was great and wished it stayed around for more. we have so many police shows, but none set in the 70's. the characters, the actors were all great and there were touches of greatness in many eps. while the last was merely ok, i just think it is hard to end something that had a bit of a cult following and so quickly after it was announced to be cancelled. given more time and another season i think the show would have caught on better.

I would love to have a show that focused on cops in the 70's without all the extra stuff Life on Mars had with him being from the future.

Saw the title and came here to post Heroes. I also think 24 and Prison Break started out great but lost their way (24 due to keeping characters past the point where they were plausibly still in the story, and Prison Break after they actually broke out.)

I loved Murder One's first season. Of course serialized dramas are hard to keep up with so ABC decided to retool to self-contained episodes and replace the lead which led to it being canceled the second season.

Dead Like Me
Desperate Housewives
Ugly Betty
Battlestar Galactica
Buffy the Vampire Slayer

I would agree with this comment back in 2007. However, Season 7 was a major comeback season. Ratings were up and it overtook Heroes in popularity in the Monday at 9pm timeslot. Moving it out of LA to Washington DC and hiring Annie Wersching as Co-lead with Kiefer Sutherland made it one of the best seasons since season 5. Season 8, which is most likely the final one, appears to have a promising premise as well being set in New York City.

Dark Angel - Jessica Alba's hotness couldn't get me to stick around after they introduced Joshua and the other transgenics.

Heroes gets my vote, as well.

Add me for Heroes. Stopped watching midway through season two because I had no idea what was going on and really didn't care.

Alias. After the big twist at the end of season2, its all down the toilet from there (hell, i don't even remember, did they ever really explain what happened?