As a fan, it's what you wait for: those moments when potential turns into production, when raw talent gets harnessed and put to consistent, brilliant use. The sportswriter Bill Simmons calls it The Leap, but the phenomenon exists just as much in the world of entertainment: think Prince with "Purple Rain," or Chris Rock with his "Bring the Pain" special, or season 4 of "Seinfeld."

The pantheon-level TV dramas for the most part haven't needed to make The Leap. You knew that "The Sopranos," "The Wire," "Deadwood" and "Mad Men" were special by halfway through their first seasons, sometimes just after their pilot episodes.

"Breaking Bad," though, took its time. Took its time and steadily improved. Started as a strange but fascinating little show carried largely by a career-redefining performance from former "Malcolm in the Middle" dad Bryan Cranston as a cancer-afflicted chemistry teacher turned aspiring meth lord. Got better as its truncated first season went along, then began to truly find itself in its second season.

Then came the third season, and the level of confidence the creative team (led by writer Vince Gilligan) had developed in that second year turned into full-blown, marvelous audacity. Anything they wanted to do, it seems, they did, and did brilliantly.

They introduced two larger-than-life Mexican assassins (known only as the Cousins) who were relentlessly pursuing Cranston's Walter White, then bumped them off midway through the season, and somehow the show got better without them. They played the moment where Walter confessed his criminal career to estranged wife Skyler (Anna Gunn) - a seismic event for the series, and one Walt had been dreading forever - as a joke, and the laughs came even as it became clear what a horror this was for Skyler. Just as Walt was starting to seem like a genuinely dangerous criminal, they turned him into a glorified clock-puncher, mass-producing his distinctive blue meth in a hi-tech lab for calculating distributor Gus Fring (Giancarlo Esposito), and Walt's prolonged emasculation only made the moment where he returned to his outlaw ways feel incredibly cathartic.

For goodness' sake, they devoted an entire episode late in the season to Walt and his sidekick Jesse (Aaron Paul) trying to catch a fly that had invaded their lab - and it was as riveting and moving an hour of television as aired anywhere that year.

That was their Leap year, the season when you just couldn't wait to see what these people were going to do next - couldn't wait to see "Breaking Bad," period.

It was the year when Paul rightly won an Emmy to go along with the three Cranston has on his shelf, when Gunn and Dean Norris (as Walt's DEA agent brother-in-law Hank) deserved to be nominated alongside them, when the show's brilliant director of photography Michael Slovis managed to consistently top his stunning desert compositions, when directors like Michelle MacLaren put together incredible time-capsule sequences like the parking lot gunfight between Hank and the Cousins.

And if I've spent the last 500+ words talking about the third season of "Breaking Bad," rather than the fourth, which debuts Sunday night at 10 on AMC, it's for two reasons:

1)The third season ended on such an incredible cliffhanger, with Walt and Jesse getting very far onto Gus Fring's bad side, that I'm reluctant to say much about the three episodes I've seen for fear of giving anything away;

and

2)While some apparent Leaps turn out to just be career aberrations (Brady Anderson's 50-HR season, Elisabeth Shue in "Leaving Las Vegas"), "Breaking Bad" doesn't seem ready to step down from the pantheon level anytime soon.

At this stage of the series, Vince Gilligan and company have total command of their instrument. They know how great the show looks, they know how much their actors can give them, and they know just how much they can get away with.

There are times when the season premiere feels like an hour-long version of that agonizing sequence in season three's "One Minute" where Hank is told the Cousins are coming for him sometime in the next 60 seconds. It's an hour dominated by silence and waiting, and is so patient in pursuing its goals that I actually started giggling at one point when I realized just how committed the creative team was to making the audience hold its breath.

And then there are times in the later episodes where Walt almost feels like a supporting character on his own show, or at least just another member of a great ensemble - when we spend extra time with Skyler, or Hank's troubled wife Marie (Betsy Brandt), or Gus's right-hand man Mike (Jonathan Banks) - and it doesn't feel like we're getting cheated out of our rightful allotment of Cranston.

"Breaking Bad" is about the rot that takes place in Walt's soul as he goes deeper into the criminal world, but it's also about the corrosive effect he has on those around him. He wrecked his marriage, turned Jesse from a casual dealer into a hardcore criminal and is responsible for Hank getting shot and paralyzed and so many deaths that I've lost count. Magnificent as Cranston is, as riveting a character was Walt is, it's important to truly understand the people he's hurting, to feel the weight of his actions.

Perhaps the best glimpse into the effect Walter has on others comes in a look on the face of Mike in one of the early episodes. Since Banks joined the cast - one of three brilliant mid-series additions, along with Esposito as the implacably cool Gus and Bob Odenkirk as Walt and Jesse's shameless lawyer Saul Goodman - Mike has been presented as a tough customer who's seen it all and is fazed by exactly none of it. But there's a moment where he has a look on his face that screams, "What the hell just happened, and how did we get involved with this lunatic Walter White?" He is startled, and shaken, and for a brief moment not at all the ultimate professional who has an answer for every situation.

And in that moment of shock and horror, Mike has an expression that I imagine has been on the face of every "Breaking Bad" fan at some point or other - that feeling of "Did I really just see what I think I saw?" - only without the joy that we take in seeing this series performing at a high level that few dramas in the history of the medium have achieved.

Alan Sepinwall may be reached at sepinwall@hitfix.com