On Feb. 3, 2002, Andrew Erwin was preparing to shoot the first and only Super Bowl of his career. Working as a cameraman for ESPN, he was about to capture a duel between future NFL legends. On one sideline was , then 24 in his first of many championships to come. On the other: Kurt Warner. Two years earlier, the latter became the talk of American sports, going from undrafted rookie to grocery clerk to Midwestern arena football star to Super Bowl MVP for one of the best offenses in league history."(For) sports fans, it was always kinda the Holy Grail," Erwin says of Warner's improbable rise. "It was the epitome of any kind of underdog story."Now here was Warner, fresh off his second MVP season, looking to snag his second Lombardi Trophy in three seasons. In the end, Brady got the best of the matchup, denying the a dynasty and instead beginning one with the . But Warner's journey had already been cemented in sports Dick Butkus Jersey lore by that point. And it's not even what Erwin remembers most about that day."I was sitting there on the sidelines," he says, "and I remember before the game, watching (Kurt) look at the stands, and seeing this beautiful, spiky-haired, tough-as-nails woman sitting there -- his wife, Brenda. And I always was intrigued, like, 'I wanna know more about that story.'" Nineteen years later, that story is hitting the big screen. Erwin and his brother, Jon, have parlayed a filmmaking hobby into a career, trading sidelines for film sets, and the Warner family is at the center of their biggest project yet: " ," in theaters Christmas Day.The movie, distributed by Lionsgate and produced by Mark Ciardi ("Invincible," "Secretariat," "The Way Back"), was originally subtitled "The Kurt Warner Story" for obvious reasons. No one ascended to Super Bowl stardom quite like the Iowa-born quarterback.Not a single team called Warner during the 1994 draft. The cut him loose after a single training camp. He resorted to stocking shelves at a Hy-Vee, then spent four years of his mid-20s -- theoretically the prime of his career -- slinging pa ses in the Arena Football League and NFL Europe, both now defunct. And then, just like that, he was the man. Forced into action with the Rams after starter Trent Green tore his ACL in the 1999 preseason, Warner proceeded Dan Hampton Jersey to headline "The Greatest Show on Turf," posting historic numbers (4,353 yards, 41 touchdowns, 13 interceptions) that still look elite in today's pa s-happy game. He capped his breakout by leading his team to its first Super Bowl win in nearly 50 years."American Underdog" certainly pays tribute to this real-life gridiron fantasy. The Erwin Brothers stage Warner's AFL stint with proper ridiculousne s; his arena debut plays like a kind of rural circus, with Kurt strolling past live farm animals on his way to the field, all while "Get Ready for This" blares '90s dance vibes. Meanwhile, a culminating act involving Warner's famous Rams debut is smartly intercut with real game footage, reviving the unlikely stakes of a Midwestern castoff taking on Ray Lewis and the . Longtime Rams fans will appreciate cameos of familiar names like Marshall Faulk and Isaac Bruce, or recreated CBS play-by-play from ."Holy cow, that day, when I came in," an emotional Johnson told the Erwins upon returning for the film, "I was a young announcer, and I thought I'd been given this gift of this great game of Ray Lewis versus Trent Green, and Trent Green gets hurt ... Cordarrelle Patterson Jersey and I thought it was gonna be a clunker of a game. And then all of a sudden, the game came to life, and I had no clue that one day it would be the ending of a major motion picture." And yet this isn't a movie about football as much as a movie about family. Why? Because this is Kurt Warner's story, remember. This is how he tells it. This is how he lived it. It's his biopic, and in his eyes, his story would never even exist if not for those by his side."Kurt and Brenda had us over to their house in Phoenix," director Andrew Erwin explains, "and we sat down, and the first thing that (co-director) Jon asked them is, 'What do you see your story as?' And Kurt said, 'I want people to know about the struggle we had as a family, how we fought to stay together. With me and Brenda, it's our partnership, and it's really about the relationship (we) had with my son, Zack.'"Kurt met Brenda while he was in college at Northern Iowa, and they married while he played for the AFL's Iowa Barnstormers. Brenda was previously divorced with two kids, discharged from the Marines after her ex-husband accidentally dropped their son, Zack, leaving the little boy blind from a traumatic brain injury. Brenda had also endured infidelity and, later, the tragic lo s of her parents. Long before Kurt became a household name, this woman and her son became his truest teammates. "We definitely have a lot of cool football stuff in the movie," says Zachary Levi ("Shazam!"), who plays Warner in the title role. "But I've been telling people, it's like 25 percent football, but it's 75 percent real life. It's falling in love, it's romance, it's then Tarik Cohen Jersey : what does that relationship look like when there's an actual family unit that starts being created? What is it like for Kurt to then be a part of helping support that family and love that family through thick and thin? There are tough years where they were literally pinching pennies for gas money. That is really the heart of what this story is about. The easy visual is, well, 'American Underdog,' that's Kurt. But the reality is, there are many underdogs in the movie. Kurt is one of them. Brenda is another."And Zack? He's the most important of them all."This movie was never gonna be made if Zack's story wasn't told," Kurt says. "So many sports movies, I feel like the story is, 'Here's the young man, and he's trying to make his dad proud of him.' Like, we're all trying to make Dad proud of us. (But) I was trying to make my son proud of me. He was the one that was teaching me and inspiring me. And that, to me, is such a huge me sage, because we think to ourselves, 'I'm in the position of leadership. I'm the one that has to lead. I have to inspire. I have to teach.' And, to me, need to be taught and inspired and learn from anybody and everybody that God puts on our path. And Zack did that for Brenda and myself.""From Day One, it's like, we're not making a movie just to make a movie, the rags-to-riches (story)," Kurt continues. "The right movie was that relationship: Brenda to Zack, me and Zack, and how he brought us together in some unique ways." It's no wonder that Warner's bond with his adopted son is the most moving piece of "American Underdog." Eleven-year-old Hayden Zaller, who is also blind, portrays Zack in his big-screen debut. At every momentous turn of Warner's Chase Daniel Jersey on-field journey, the little boy's radiant innocence is there. When Kurt marries Brenda, all worries around the QB's fading NFL prospects di sipate as Zack sings directly to his new dad at the wedding dance. And when Kurt is abou