We all have our favorite television shows but, let's face it, sometimes it takes them an awful lot to get there. And while some shows - Firefly for instance - are genius all the way through (at least in some people's opinion), others falter, they rise up only to fall flat on their ass, before climbing up to great heights again. Thus I pose the question; what's some of the greatest season of television you've seen? And which are the worst?

Plus points for saying "this show starts slow, but man I have never enjoyed anything as much as x season".

The sad thing about this question is that all those shows where you marathoned everything (for me, my favorite show is Twin Peaks, but that's like one big season for me. I have no recollection of "HOLY SHIT THAT'S THE END OF SEASON ONE?" or something. Just a long, continuous story with some ups and downs. Similarly Arrested Development, my favorite sitcom of all time) are sort of hard to pick out seasons on.

Mine are probably...
* Doctor Who Season 6 - there's not a bad episode in there, though "The Curse of the Black Spot", "Night Terrors" and the flesh-two-parter are somewhat weaker than the rest.
* Slings and Arrows Season 2 - just might be the perfect season of television. Everything works. Marvelous.
* LOST Season 4 and 5 - I watched the entire fourth season in a day, and it remains my favorite season of the show. I saw season 5 when it aired, week-to-week, and I have rarely had so much fun discussing and obsessing and talking about a show. In a long period of time, it was all I thought about. Excellent, hilarious and truly fantastic seasons.
* Community Season 2 and 3 - Again, I saw this when it aired, which makes it easier to remember which seasons I liked the most, and while season 1 is great too - it's what made me fall in love with the show - these two seasons were where it hit its stride. Every episode is hilarious, the characters are great, the plots are widely different and it's able to do everything from western-paintball-episodes to Space-episodes to Conspiracy Thrillers and whatnot, while still delivering heartfelt and emotionally great storylines in addition to all the silliness and plotness. Just brilliant.
* Supernatural Season 4 and 5 - That whole Heaven vs. Hell-arc kicked in and man was it ever so glorious.
* The Vampire Diaries Season 2 and 3 - Listen; I really love this show and the current season is by no means bad, but the middle part of it has really sagged. It got its groove back a couple of episodes ago though, and I hope it finishes as strongly as it began. But nothing beats these two seasons. They were incredibly. I don't remember that much from season 2 - I should probably rewatch it - but after dragging my ass through the first (lame) season, I sprinted through season 2 in a weekend. Twenty plus episodes. In one weekend. That alone says it all. Season 3 was the first season I saw week-to-week, and I loved the whole Alaric-plot. It wasn't quite as good as season 2, but I still have a lot of fond memories of it.

These are some of mine - I could probably come up with more, but this is it for now. And please, don't bother with things that either only ran for one season - like Firefly, Rubicon, Terriers, Awake etc; I know you loved them, as did I, but this isn't the thread for that - or things that are still in their first or second season. This is a thread for LONG shows. And please, don't even bother mentioning Breaking Bad. We all know that's been on a steady upward curve all the way. :P