First-year head coach Matt Nagy is quick with a smile and quicker to draw up a wild, creative play that gives defensive players a chance to score some TDs. Throw in a seven-game improvement and a team-wide passion for dance, and no team in the NFL is having more fun than the Chicago Bears.

LAKE FOREST, Ill. — Vic Fangio gestures to the screen showing a clip of the Rams offense. It’s 9 a.m. and he’s about to introduce the first concept of Friday’s defensive install when—

Knock. Knock.

At that sound, the defensive players rustle in their seats and chatter with playful excitement, like a classroom of squirmy schoolkids. They recognize those two loud knocks, and they know exactly who is at the door.

The visitor outside pauses for a beat, then cracks the door and sticks his head inside. Now the players are really riled up. They look around the room, trying to predict who might get called on this time.

“Sorry Coach,” Matt Nagy nods at Fangio. “But I’m going to need 9-0, 9-5, 9-6, 9-8.”

The four defensive linemen—Jonathan Bullard (uniform No. 90), Roy Robertson-Harris (95), Akiem Hicks (96) and Bilal Nichols(98)—practically jump out of their chairs. Fangio sighs and shakes his head. Here we go again.

“Won’t be long with them Coach,” Nagy assures his no-nonsense defensive coordinator. Fangio shrugs in surrender and excuses them from his room.

The head coach and the four defensive linemen trot down the hall and through a door on the left to the team room where the offense meets. Nagy hasn’t revealed the play yet to the offense, so everyone—aside from the quarterbacks, who have already seen everything—is shocked when the four big guys thunder into the room. They whoop and applaud for the newest members of the offense. “It’s entertainment for the offense, for us to come into their world and get a piece of their action,” Hicks says. “It’s fun for them.”

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This Fun Friday routine happens so often at Halas Hall that it’s nearly a weekly ritual. Defensive players look forward to it all week. Safety Eddie Jackson was the first to get picked (he lined up at slot receiver for one snap in Week 9), then Hicks (on “Freezer Left,” took a handoff and scored against the Giants in Week 13), and then, “more people, more people, more people” says Bullard.

“As much as we are used to it, when he knocks, it still surprises us,” says cornerback Kyle Fuller. “You’re just wondering, Who he is going to call?”

Adds linebacker Danny Trevathan: “We’re totally focused on defense. But you just never know. You hear that distinct knock, and it might be your calling to be great.”

After four straight years of finishing last in the NFC North, Chicago won the division and is headed to the playoffs for the first time since the 2010 season. The catalyst has been the man players describe as a “ball of excitement”—the 40-year-old, first-year head coach who has awoken a dormant Bears franchise one knock at a time.

In each of his first five seasons in Chicago, when this time of year rolled around, guard Kyle Long would be preparing to get the hell out of town. “You’re starting to figure out which pipes you’re going to shut off in your house and which ones you have to leave on and which ones you have to check on throughout the winter,” Long told reporters the week of Chicago’s regular-season finale. “But we’re going to be here for a while, so get settled in. The playoffs are coming.”

Though Chicago’s success this season has taken many by surprise, the front office had been building with an eye on 2018. The young defense was a top-10 unit in 2017. Quarterback Mitchell Trubisky was expected to take a step forward in his second season. All they needed was some better receivers and, of course, the right head coach. Even before the Khalil Mack trade, players say they could feel things were changing during training camp. And when trying to identify the launching point for this season, many point to the season-opening loss in Green Bay.

“The first time we came together as a group, I looked around the room and I had a sense then, but I wasn’t completely sure of it until the first game, Green Bay,” Trevathan says. “We didn't win it, but I felt like it was a great game for us to get going.”

Daniel Bartel/Icon Sportswire/Getty Images

Chicago’s loss at Green Bay was heart-breaking. The Bears squandered a 20-point lead despite Aaron Rodgers limping through the second half after being carted off with a knee injury earlier in the game. But as far as losses go, it was an extremely encouraging performance—Trubisky played a solid first half and so did the defense, with Mack playing a major role in just his eighth day with the team.

“When we played the Packers, I thought, O.K., we have a really good team,” offensive lineman Bradley Sowell says. “But the question was, could we get over the hurdle of, Hey, now we show up and expect to win rather than feeling we’re going to get in every game and then lose?”

Says Nagy: “Guys were searching for some leadership in that situation. They were looking for direction. How do we handle this? Man, this is tough. We just fought so hard, such an emotional game and we did everything you asked us to do and then we ended up losing here. So now what?”

Nagy seized the moment, reminding his guys there were 15 more regular season games ahead, and they needed to use the sting of this so close moment as motivation to finish every game going forward.

“You can’t really judge a coach when everything is going good,” says safety Adrian Amos. “When adversity happens, that’s how I gauge somebody. When stuff goes wrong, what’s your message? How do you change up? Do you have the same energy you had before?”

Nagy’s boundless energy didn’t wane after that loss, it only grew from there, and the Bears rallied to beat Seattle 24-17 at home the following week.

“I like hearing that that’s when they, as a team, felt they started believing,” Nagy says. “You hear things but you’re not fully all-in, and I think that is probably the start of when they started buying into everything. What my messages were, what our coaches’ messages were, and started believing in one another. And then, strength in numbers, everybody started believing and it’s powerful.”

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Amukamara and the defense's Thanksgiving Day tribute to Motown was one of the NFL's best celebrations of the year. Amy Lemus/NurPhoto/Getty Images

Six days before the Packers loss, Virginia McCaskey, the team’s 95-year-old owner, spoke to the team. Part of her message was about being confident, because great Bears teams of the past never lacked in confidence. This team has stacked wins and developed a swagger reminiscent of the untouchable ’85 Bears.

When players returned to the locker room after beating Seattle for the first win of the season, they were surprised to find the lights off, a disco ball spinning and music blaring. This was the first “Club Dub,” Chicago’s now viral post-game locker room celebration, an idea Nagy got from a conversation with Cubs manager Joe Maddon, who advised him to celebrate and enjoy every single win.

“I started out as the guy in the back who was just bobbin’,” Sowell says. “Then as we started to win more and more, I really started buying into the culture and then I started dancing in the circle, trying some new things. This is the culture of our team. If you don’t dance when you score here, you’re going to get booed.”

Nagy noticed that his players loved to dance, so he decided to create a weekly competition to foster more of that self-expression. He draws two offensive names and two defensive names out of a hat each Tuesday, and the chosen players have the rest of the week to pick out a song and prepare their routine. The two sides square off on the orange C logo on the locker room carpet every Saturday morning, with three Bears staffers serving as a panel of judges. The biggest upset of the season came when practice squad linebacker Josh Woods beat running back Tarik Cohen. Cohen is one of the team’s best dancers, and that day he performed a dance battle scene from the 2004 movie You Got Served. Woods stunned the audience and the judges by matching Cohen’s backflip, stealing a win for the defense. “It was a fluke,” Cohen says. “Definitely rigged.”

Cohen's backflips have helped him to a reputation as one of the team's best dancers (though it didn't help him in one of the locker-room dance competition). Joe Robbins/Getty Images

The fun extends to the meeting rooms. Nagy often sources player input when designing the unconventional plays that have confused defenses and stirred up Bears players. The blowout win over the Bucs in Week 4 featured Chicago’s first truly wacky touchdown play of the season, “Willy Wonka,” which featured two quarterbacks, Trubisky and No. 2 QB Chase Daniel, in shotgun. Trubisky pitched the ball to receiver Taylor Gabriel, running left to right across the formation, and then faked a zone-read to Daniel.

On the Thursday night of that week, Nagy, offensive coordinator Mark Helfrich, quarterbacks coach Dave Ragone, and the quarterbacks met to review plays. They decided that the play, as it existed at the time (11 personnel—one running back, one tight end, three receivers), was too normal. “We were like, how can we mix it up?” Daniel says. “One thing led to another and then two quarterbacks got in the game and we're shifting and motioning and we were three times jetting. It’s cool because you feel some accountability with the play and you make it work.”

Trubisky named that play, randomly blurting out “Willy Wonka” as a suggestion. “There was zero background,” Daniel says. “He was just like, Oh, Willy Wonka! Well, O.K. then.”

Nagy has most often used his creative calls in the red zone, and the Bears have scored four touchdowns and a two-point conversion off trick plays this season. Trevathan says he's been plucked out of the defensive meeting room twice this season, but hasn't had his play called on the field yet. Two Bears players brought up Mack's name when talking about trick plays, suggesting there are several more surprises left in Nagy's arsenal. Nagy has said his play-calling is aggressive, and he understands the risk involved. Sometimes his fourth-down attempts fail, or the opponent sniffs out the fake punt, or a running back fumbles after taking a direct snap. Even when he’s accused of getting too cute with his calls, he reiterates that he won’t change his philosophy, because he’s confident in his coaching identity. In the corner of every play sheet he uses in games are two words, large font, in colorful, capital letters: BE YOU.

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There’s a term Bears staffers use to describe Khalil Mack: “multiplier.” He doesn’t just improve the team at outside linebacker, but he lifts the play of the rest of the defense. When the Bears pulled off the shocking trade for Mack, just eight days before the regular season began, the turnaround accelerated to the final stage. Seeing Mack on the practice field for the first time was enough for Bears staffers and players to know they were ready; Mack had pushed them over the top.

“Even before 52 got here, I knew we had the roster, I knew we had the pieces on defense,” Long told The MMQB. “And then when Khalil got here, it was just icing on top, the cherry on top. We had it all, the depth, talent and ambition.”

Bears cornerbacks have particularly benefited from Mack’s presence, because his presence forces quarterbacks to get the ball out quicker and force them into bad decisions. Fuller had two interceptions in each of the last two seasons. He now leads the league with seven picks. Fuller’s counterpart, Prince Amukamara, didn’t have a single interception in 2017, his first year in Chicago, and now he has three. The Bears defense leads the league with 36 takeaways and their 27 interceptions is six more than the second-place Dolphins’ total. Fangio’s unit is also third in total defense, second in yards per play allowed, and first in defensive points allowed. The Bears are the only team in the league whose defense ranks in the top 10 of every major statistical category.

Mack leads the league with six forced fumbles and leads the team with 12.5 sacks. He’s elevated the defense as a whole—Chicago has three first-time Pro Bowlers on defense this season: Hicks, Fuller and Jackson. The future for Bears defense is scary, if they stay healthy and stay together. Linebacker Roquan Smith, the eighth overall pick of the 2018 draft, missed all of training camp because of a contract holdout, but he’s improved with every game and was named a Pro Bowl alternate. Every starter is under 30 years old, and eight of the 11 are under contract through 2021. “We can be forever,” Trevathan says.

Nagy’s best move since his hiring was convincing his defensive coordinator to stay in for a fourth season in Chicago. If the 60-year-old Fangio isn’t hired away this offseason (he’ll reportedly interview for the Dolphins and Broncos head-coaching vacancies), this defense might be remembered forever in Chicago. Chicago wouldn’t be 12-4 and hosting a home playoff game without Fangio’s work.

Fangio and Fox didn’t have the best relationship. A source close to the team says there was friction between the two defensive-minded coaches, who had different philosophies. It wasn’t a toxic environment, but their differences prevented success.

Nagy, high-energy and quick to smile, is a polar opposite to the tough, serious Fangio, 20 years his senior.

“I’d say I’m more focused,” Fangio deadpanned.

But their relationship is working seamlessly because Nagy lets Fangio do his thing uninterrupted (except for a few minutes on Fridays).

“Vic is stern,” says Hicks. “He's been in the league for 30 years and he knows exactly how he wants things and he’s very set in how he wants the defense to be played. Nagy is this ball of excitement and he also has that same drive and focus, he just puts a really fun spin on it and gets guys to work together in a different way.”

“You got one on your bad side, and one on your good side,” Trevathan says, gesturing to each of his shoulders. “One that just nods at you and one that is just hyping you up all the time. But you know that both of them appreciate the game of football, they love this team and they take pride in when we play well.”

When asked to describe who the 2018 Bears are, several players repeated a variation of the same theme: selfless. That sentiment is fitting for an offense that spreads the wealth in a way few other teams in the league do. Allen Robinson leads the team with 759 receiving yards, but Cohen, a running back, led in catches (71). Gabriel is next with 67. Rookie receiver Anthony Miller has been Trubisky’s favorite end zone target, with seven touchdowns, followed closely by tight end Trey Burton with six, whereas Robinson and Gabriel have just four and two receiving touchdowns, respectively. The Bears signed Robinson to a three-year, $42-million contract to be the team’s No. 1 receiver. In each of his last two full seasons in Jacksonville, Robinson was targeted 151 times (making 80 and 73 catches). He was targeted 94 times this year (while being limited to 13 games).

“It’s different here,” says Gabriel, who Chicago signed as a free agent from Atlanta last offseason. “The way we spread the ball around, the distribution is kind of crazy because you never know who is going to have a good week. You never know who is going to do it, so a lot of fantasy owners are pretty upset with me.”

The offense is like a football Hydra, growing new heads just when an opponent thinks they have cut one off. In Week 17 at Minnesota, the Bears’ three leading receivers were out with injury for the majority of the game. Seventh-round rookie Javon Wims, who entered the game without a catch in an NFL game, hauled in two crucial third-down passes to extend a 16-play, 75-yard scoring that lasted nine minutes and sealed the Bears win.

But the main reason the Bears hired Nagy, a former Arena League quarterback and QBs coach under Andy Reid in Kansas City, was to get the most out of Trubisky. The 24-year-old signal-caller has responded to Nagy’s coaching and improved over his rookie year, but he remains frustratingly inconsistent, making the Bears the rare playoff team with a question mark at the game’s most important position.

There have been positives. Trubisky had a career-high six touchdowns against Tampa Bay in Week 4, and a career-high 355 passing yards in a Week 10 victory over Detroit. The Bears converted 41% of their third downs in the regular season, good for 11th in the NFL—that number was 44% in Trubisky’s 14 starts, and the Bears have been one of the league’s better teams on third-and-medium (4-6 yards), converting 52.7% of the time (fourth-best in the NFL), including a 50% conversion rate when throwing (tied for seventh). Trubisky has also proven to be one of the league’s best quarterbacks creating with his legs, extending plays and rushing for 421 yards on the year.

But, while Nagy’s system and play-calling have created opportunities for big plays downfield, Trubisky hasn’t been able to take advantage. Of the 33 quarterbacks who attempted at least 20 throws of 21-plus yards in the air this season, Trubisky’s 63.2 passer rating on such throws ranks 31st. More worrisome have been his poor decisions when forced off his first read; Trubisky has thrown 12 interceptions this season, and has been fortunate on a number of other mistakes that either bounced off defenders’ hands or were nullified by penalties away from the ball. Since a disastrous Sunday night performance against the Rams in Week 14—after missing two weeks with a shoulder injury, Trubisky threw for 110 yards and three interceptions on 30 attempts—the Bears have seemingly scaled back the passing game, limiting Trubisky’s risk-taking but also getting a safer, more efficient performance from their QB. Over the final three games of the regular season, he completed 75.9% of his throws with only one turnover (a lost fumble).

The Bears' playoff success could hinge on Nagy's work with his inconsistent young QB. Patrick Gorski/Icon Sportswire/Getty Images

Ragone was the only offensive coach retained from John Fox’s staff. His close relationship with Trubisky landed him an interview with Nagy, and the new head coach realized immediately that he and Ragone were similar minds that would work well together. Continuity was crucial for Trubisky’s development, and Ragone’s knowledge of the quarterback and the previous season was helpful to the new coaching staff during the transition.

“There’s a reason for that right?” says Daniel, on Ragone being the lone holdover. “His relationship with Mitch, it goes deep. They have been in the trenches together. Rags knows exactly how Mitch plays but also his emotional side. Him and Rags are just on a different level.”

Ragone and Trubisky are both from the Cleveland area, and both involved in the intense and close-knit prep football culture in Northeast Ohio. Their high schools play each other often, and because Ragone has remained close to his high school coaches, he was familiar with Trubisky, a difficult matchup for Ragone’s alma mater, St. Ignatius. “I know exactly where he grew up, he knows exactly where I grew up, “ Ragone says. “We have a lot of those similarities in how we see things, which helps our relationship on and off the field.”

Trubisky is a fiery competitor who can be very critical of himself after a bad play or series. As part of his development this season, Nagy and Ragone have been working to help him better control his emotions during games. Nagy often sounds like an overprotective father when talking about Trubisky. “I need to be that security for him and that safety for him,” he told reporters, when asked how he would prepare Trubisky for his first experience in the playoffs. “I need to be there to comfort him in all types of scenarios, whether he is playing well, whether he makes a poor decision, because it is new territory for him. He does have a lack of experience in these situations.”

Sowell (No. 79) did get his dance in before teammates mobbed him after his touchdown on "Santa's Sleigh." Jonathan Daniel/Getty Images

As the four defensive linemen settle into seats, Sowell, the backup offensive lineman, wonders to himself, What in the world? What is this play going to be? Fridays are red zone days, so all Sowell knows is that this is a scoring play.

Nagy puts the play up on the screen. “Santa’s Sleigh” features the four defensive linemen and Sowell in place of the five skill players typically used on offense. Trubisky will fake a handoff to Hicks and then throw the touchdown pass to Sowell.

Nagy’s motto all season has been, Be You. He’d seen Sowell’s athleticism and the way he easily catches passes from Mack during pregame warmups. This play takes advantage of exactly who Sowell is as an athlete. Nagy calls the play on Sunday Night Football against the Rams, and Sowell is shocked that his coach trusts him to deliver in such an important game. He catches Trubisky’s pass, and unleashes a goofy dance in the end zone.

“I’ve been on a lot of teams and this team has a different feel to it,” Sowell says. “It’s been one of the funnest. I seriously do not want this season to end. I want to play 10 more games with this team, any day.”

That’s the biggest problem for a collection of players having the time of their lives: No matter what happens in January, there are no more than four more games left in this season.

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