The shows on this list may not have been perfect for their entire runs (or may simply be too young to feel deserving of a spot on the main lists), but for at least one season, they were pretty damn terrific.

"24" season 1 (Fox): The degree of difficulty seemed impossibly high: not only a single plot told over an entire season (which had been tried, to very limited success, with ABC's "Murder One"), but one told in real time, and an action series (in a medium where action is tough to do well on a regular basis), to boot? Yet the first season of "24" mostly pulled it all off (give or take Teri's amnesia and Kim's second kidnapping), thanks to Kiefer Sutherland's almost feral performance as Jack Bauer and a production team that knew exactly how to tell their story, even if they didn't always know what that story would be (again, see Teri's amnesia). They've repeated that formula, with diminishing returns, for six additional seasons and a lackluster TV-movie, but the self-parody the show has become can't take away from how thrilling and bravura Jack's first busy day was.

"Sons of Anarchy" season 2 (FX): This outlaw biker version of "Hamlet" roared through its second season by bringing in a group of white supremacists playing a divide-and-conquer strategy against the Sons, at a time when the club was already on the verge of splintering apart. The action was fierce, the performances – particularly from Katey Sagal, Charlie Hunnam, Ron Perlman and Maggie Siff as the Sons' unofficial royal family – even fiercer. And for a drama about a gang of hard, at times homicidal, men, the series could be almost shockingly tender in showing how much the Sons' violent lifestyle weighed on the club members and their loved ones.

"House" season 1 (Fox): As "CSI" tore up the Nielsen ratings, Fox introduced what might as well have been called "CSI: MD," recasting the hospital drama format as a special-effects-heavy detective thriller, with crippled, sarcastic Dr. House (Hugh Laurie) racing against the clock to identify the obscure disease ailing his latest liar of a patient. "House" is strongest when it focuses on Laurie's wonderful performance as a miserable bastard who has to suffer for always being the smartest man in the room, and on the twists and turns of the cases, and weakest when the show tries to do story arcs or turn the spotlight to the frustrated members of House's team. And while season one did a bit of each, it did both much less than later seasons, and the formula of the cases was much fresher than it would become a hundred or so episodes later.

"Chuck" season 2 (NBC): One of several shows on this list to make a few small tweaks after their first season that paid huge dividends in the second, "Chuck" – about an IT nerd (Zachary Levi) who accidentally becomes America's most important spy – created a fanbase so passionate, they organized one of the more successful Save Our Show campaigns in TV history when it looked like NBC wouldn't renew it.

"Breaking Bad" season 2 (AMC): The first season of this drama about a dying high school chemistry teacher turned meth dealer surrounded Bryan Cranston's gripping lead performance with a lot of fuzzy storytelling. The series then returned from the writers strike with a clearer sense of purpose, a richer and more assured visual style, stronger writing for the supporting characters (notably Aaron Paul as Cranston's reluctant sidekick) and a cold, calculated view of a drug lord's world. If the upcoming third season can maintain that level of daring, "Breaking Bad" is just as worthy an heir to "The Sopranos" as fellow AMC drama "Mad Men."

"Dexter" season 1 (Showtime): Like "24," "Dexter" is a show that would have been better off made in a business model that didn't demand that TV shows just keep going and going as long as the ratings are there, quality be damned. As Dexter, police scientist by day, serial killer by night, Michael C. Hall is never less than riveting. But the longer the show has been on the air, the less dangerous it and its main character seem.

"How I Met Your Mother" season 2 (CBS): The titural search for the future mother of Ted Mosby's (Josh Radnor) children is often the least interesting part of this sitcom, so it makes sense that its funniest season would be one where the search was put on hold all year. With Ted dating Robin (Cobie Smulders), whom viewers already knew was not the mother, the writers could focus on the other, more appealing parts of the show: amateur sociology , or practical jokes , or musical parodies (Robin is revealed to be an Alanis-esque former Canadian teen pop star), or silly, shocking physical comedy . In the '90s, many shows got the unfortunate, undeserving tag as "the next 'Friends.'" The media stopped doing that by the time "HIMYM" came along, but if ever there was a show that was a proper spiritual descendant, it's this one, and this season in particular.

"Grey's Anatomy" season 2 (ABC): The medical drama's abbreviated first season was a surprise hit – though, as a blend of the best parts of "ER