Mike Vick calls it PlanC.

You might refer to it as being in the zone or on fire or just plain sick. Whatever you label it, you know it when you see it. It renders rampaging blitzers gelatinous. It guides a 25-yard pass through a mail slot on third-and-24. It's the hot streak that carries a quarterback -- and his team -- deep into the playoffs. It's QB Mojo. And it gives quarterbacks an aura that amps a stadium and a city. When Vick -- an MVP candidate in only his second season -- needs to plug in, he goes to PlanC.

"A is run and B is pass," Vick says modestly.

	When you have your mojo, everything falls into place ...

"And C is me."

As he says this, walking down a corridor at the team's practice facility north of Atlanta, Vick suddenly stops in his tracks. His eyes pinch shut, his chin goes up, his chest puffs out and a thin smile stretches across his face.

QB Mojo is like carbon monoxide -- odorless and colorless, but lethal to defenses. Still, there are a few athletes who give off a telltale sign when their Mojo's rising. Michael Jordan hung that tongue. Tiger Woods pistons those fists.

When Vick gets sick, you see that cool Shaft smile.

He flashed it in the huddle in Pittsburgh on Nov.10, when the Falcons -- then 5–3 -- were down by 17 in the fourth quarter and their season was teetering on the brink. Vick leaned into the huddle and told his teammates, "We aren't losing this game." Just like that, he invoked Plan C. "Yep," says Vick. "When it's time for me to create something, give it a little edge, throw some schoolyard into it, freestyle a bit -- that's Plan C."

For the next 12:34, every time he picked up the ball, the laces felt custom-sculpted for his grip. He rushed three times for 30 yards and a touchdown. He completed seven of his final 13 passes for 120 yards, including a 35-yard leather laser to wideout Shawn Jefferson on third-and-24. And he wound up salvaging a tie that's turned out to be crucial as the Falcons race for a playoff spot.

A 12-year vet, Jefferson stood there as players swirled around him, marveling at how Vick had delivered that third-down pass. "When a quarterback is in a zone, he can't miss," Jefferson says. "There's a look in his eye, a swagger in his walk, a tone to his voice. Every throw, every run, every decision is perfect. It's another level that no one else can get to, and you just try to jump on his back and go along for the ride."

That ride is something quarterbacks describe using words with an almost religious quality: faith, belief, hope, a sense of transcendence above the grunts and grass. "You feel calm and businesslike going through it," says Pittsburgh's Tommy Maddox. "You're very ... in the moment." Says Hall of Fame quarterback Terry Bradshaw, "It's about the belief a team has in their guy. All you want as a player is a chance, and a guy like Vick gives you that hope."

Notice that no one mentions stats. Vick has thrown only 13 touchdown passes, the same as part-time starters Rodney Peete (Carolina) and Jim Miller (Chicago), neither of whom will get to the playoffs -- or to Canton. QB Mojo gets its value from the tangible way it affects the rest of the team. "Everyone believes in Michael Vick," says Bradshaw. "Now, he won't always do it, but the belief that he might elevates those around him."

Eagles coach Andy Reid says it all stems from the core of the quarterback himself. It's why the most gifted passers don't always make great gamers. Cases in point: Ryan Leaf, Jeff George, David Klingler. Players won't follow phonies. They gravitate naturally to the real thing like metal shavings to a magnet.

"Donovan McNabb is a quality person with no barriers," says Reid. "Not just on the field. I'm talking race, religion, position. He hangs out with everyone. Defensive linemen, offensive guys, rookies, veterans, Pro Bowl guys, coaches, equipment guys, it doesn't matter. People give more of themselves to guys like that."

There's a cerebral element to QB Mojo as well. Recognizing blitzes and cover schemes, making the right audibles on that first drive -- all help create a sense that the game is moving in slow motion around him. A detail-obsessed vet like Rich Gannon gets rolling after completing several crisp short passes, connections he first made in his mind while immersed in a regimen of exhaustive film study.

"Gannon can go 13-for-13 quick and work himself into a zone," says Falcons cornerback Ray Buchanan. "Suddenly your corners are on their heels, the defensive coordinator is second-guessing himself, and no one knows how to make it stop. Guys come to the huddle saying, 'Uh-oh, Gannon's got the Mojo.'" Teams like the Broncos, Eagles and 49ers script their first 15 offensive plays in search of a Mojo dose, because if you find it early, you'll win. The team that scored the first offensive TD has won the past four Super Bowls.

For a guy like Maddox, who's propelled himself from first-round bust with the Broncos to Steeltown folk hero, the Mojo comes when he's got nothing to lose -- like in that November game against Vick and the Falcons. "Sometimes you get down on yourself and you just lay it on the line," he says. "Once I start winging it, it starts clicking."

For others it's more visceral: the grip of the ball, the first time they groove a pass in warmups and see the tight spin of those laces, even the smell of the grass, the sound of the crowd or those tiny stars that pop up after a head butt from a teammate -- all can conspire to trigger a sudden sense of infallibility.

Vick takes a reading during warmups: How do I feel? How am I throwing the ball? What's the game atmosphere like? The weather? The crowd? But big plays flick the switch for him. A spark from special teams, a big hit on defense, even a bone-crunching block can, he says, "take me to that zone."

It doesn't matter how a quarterback gets there as long as he does, because unprecedented parity in the NFL means one solid streak can get you a trip to Disneyland. The past two Super Bowl champions, the Ravens and Patriots, didn't dominate their entire seasons the way the old-school dynasties would. They just caught an emotional wave at the right time and rode it. That's why QB Mojo is so vital to postseason success. You can practically use it to handicap teams leading up to the playoffs.

Vick? Got it. Gannon? Got it. Brett Favre? Defines it. McNabb? He's got so much he passed some to his backups, Koy Detmer and A.J. Feeley. Steve McNair? McMojo. Kurt Warner? Had it, lost it. Peyton Manning? Needs it. Brad Johnson? Finally found some. "It's a special, almost magical thing," says Bucs coach Jon Gruden, a former college quarterback at Dayton.

Then there's Mojo-in-a-minute. Think back to Tom Brady in last season's Super Bowl. In the game's final 1:21, with no timeouts left, he completed five of six passes (not including two spikes) to move the Patriots 53 yards for the game-clinching kick. The drive's key moment was a 23-yard pass to Troy Brown down to the Rams' 36. The play, 64 Max All In, calls for the linemen to hold their blocks a few more Mississippis, and for the receiver to get free in the dead part of the zone, 20 yards downfield and over the middle. It also calls for the quarterback to gut it out in the pocket long enough for his guy to get open -- all in the final seconds of the season's megagame. "What Tom Brady is doing right now is giving me goose bumps," John Madden said up in the booth.

	Kurt Warner has won back his starting job, but his margin for error will be slim.

The dark side of QB Mojo is that it can turn into a Mofo with no warning. Usually the end comes in the form of a heat- seeking linebacker or a cornerback flashing into what was supposed to be an empty zone. Sometimes, though, the tiniest things can burst the bubble: a bobbled snap, a bad read, a route run wrong. All of a sudden a quarterback's legs feel heavy, his head's fogged in and he feels like the center just snapped him a frozen Butterball turkey. "That's the great mystery to this vibe," says Steelers backup and former Detroit starter Charlie Batch. "There's no way to turn it off and on." It's like blackjack. One minute you're on fire, you can't lose. The next? Busted. Home for the holidays.

Just ask Warner. A year ago he was the toast of the NFL. League MVP, 4,830 passing yards, 36 touchdown passes. Now, with a mangled hand and 11 interceptions and three touchdowns, he's on injured reserve, done for the year and possible trade bait in the off-season. "Warner was a guy people said would have Mojo forever," says Buchanan. "That shows you what this stuff is like. Man, he lost his Mojo -- all of it -- in about a minute."

When that happens, the Jake Plummer syndrome can get you. That's the urge to get it all back with one big throw, one that often ends up in the hands of a defender. "When it's leaving, you know it's going," says Batch. "You try to talk yourself out of it. You say, 'Please, let's get up now, please, let's get this going again'. But the ball doesn't feel right. You know it. You deny it. But you know."

Nobody can shake QB Mojo out of guys like Favre and McNair. They're like those high-compression rubber balls -- the harder you throw them down, the higher and faster they bounce back. A pulled ribcage muscle and a severe case of turf toe kept McNair out of practice for two weeks before the Titans faced the Colts on Dec. 8 with first place in the AFC South on the line. He endured a pain-numbing injection and then stepped up to complete 19 of 23 for 237 yards and a TD in a 27-17 win.

"I can't even explain my game when I'm injured," says McNair. "When you're in pain, you stay more focused on what you have to do."

McNair says he relies on some defining qualities: calmness, clarity and confidence (maybe that's why Vick calls it Plan C), governed by a sense of urgency and a gunslinger mentality. All come together when the game's on the line. Vick has run the two-minute offense eight times so far this season, and the Falcons have scored on seven of those drives (four touchdowns, three field goals.) The Pro Football Hall of Fame asked for his shoes after he ran for 173 yards against Minnesota to break a 30-year-old record for quarterbacks, including the game-winning, 46-yard TD run in OT. "When Mike is in the zone," says Jefferson, "crazy stuff can happen."

Vick is so laid-back, sometimes you want to poke him to see if he's awake. But get him talking about his Mojo, and he's all air passes, shimmy-shakes and glances into an imaginary secondary. "It feels so good," he says. "I'm sweating, pounding my fist, yelling, 'Let's do this! Let's go! Let's make this happen!' You don't want to leave the field. I've felt that way this year against Green Bay, Pittsburgh, Cincinnati, Carolina twice, New Orleans ... "

So basically, Mike, you've been in a zone -- operating on Plan C, that is -- the whole season?

"Yeah," he says. "Almost."

When hasn't he? In a 34-10 Week 14 beating by Tampa Bay, Vick learned just how temperamental Mr. Mojo can be. The lesson was reaffirmed in Week 15 when, despite a last-second, 12-yard TD pass from Vick to Trevor Gaylor that forced overtime against Seattle, the Falcons lost again. As Vick watched Falcons kicker Jay Feely miss a 36-yarder that would have won the game, he found out that kickers -- usually the ones on your team -- can be kryptonite to Mojo. Better to finish the job yourself.

Still, Vick won't get desperate. "It's a fragile thing for a lot of guys," says Falcons coach Dan Reeves. "But the better the athlete, the longer he stays in the zone." So Vick has little to worry about.

Others aren't so lucky. What happens when nothing works and the Mojo doesn't return?

"All you can do," says Bradshaw, "is retire."

This article appears in the January 6 issue of ESPN The Magazine.