For what appears at first to be a patriotic war film, “Billy Lynn’s Long Halftime Walk” is really an anti-war film. For a film that mostly takes place in a football stadium, while a game is going on, it’s surprisingly anti-football. The same goes for both subjects in Ben Fountain’s novel, upon which the film is based.

Seen through the eyes of its 19-year-old protagonist, Billy (first-time British actor Joe Alwyn), Ang Lee’s war-sports film does a lot of wandering around, jumping back and forth between a heroic deed done by a squad of soldiers on an Iraq battlefield in October, 2004, and events that take place on the “Victory Tour” the eight men are sent on across America a month later, culminating with a final stop at that Dallas Cowboys game, before they head back to Iraq.

The men became heroes when, against all odds, they rescued some fellow soldiers in the midst of a firefight. The mission was caught on camera, went viral, made America proud, and then there they were, the men of Bravo, waiting in the stands, not the least bit interested in the game, or waiting backstage before halftime, with no idea of what they’re supposed to do when the TV cameras are trained on them, unaware that they’re really only there for ratings, that they’re propagandist props, ordered — by TV executives and the stadium stage crew — to just stand there while Destiny’s Child sings and shimmies in front of them.

But that’s not much to build a movie or a book on, so author Ben Fountain and screenwriter Jean-Christophe Castelli, who adapted the book, infuse it with flashbacks to earlier moments during the tour across the States, stopping for a while on the time that Billy visits his family in Texas, and to what went on in Iraq that put them on that tour.

Ang Lee (“Life of Pi,” “Brokeback Mountain”) continues his usually insightful exploration of the human condition, but does it this time with all sorts of modern technology at his side. He shot the film digitally, in 3D, and used a high-speed frame rate to project it that gives the film exceptional clarity. Unfortunately, there are only a couple of cinemas in America that are equipped to show the film the way Lee envisioned it. It’ll still look great in 2D with a regular frame rate, it just won’t be as eye-popping.

But even with the razzle dazzle of what Lee has referred to as the future of films (yes, I saw it projected the way he wanted it done), this comes across as a flattened-out affair. There’s some strong acting from Garrett Hedlund as the protective and demanding Sgt. Dime; from Steve Martin as the wealthy tightwad Cowboys owner Norm; from (far too briefly) Vin Diesel as Billy’s mentor, Sgt. Shroom; and from Kristen Stewart as Billy’s troubled and troublemaking black sheep sister Kathryn.

But Joe Alwyn rarely gets beyond looking like he’s in a daze as Billy. Perhaps that’s what the filmmaker wanted, but he becomes a drag to watch. And the uncomfortable feeling the soldiers get at the stadium spreads in a contagious way among audiences watching them.

Lee has plenty of cinematic skills on display. The effect he gets by cutting from the men in full military dress, walking through the stadium, to them in combat fatigues running through a town in Iraq, is equally remarkable and numbing. He captures great moments such as when, during a press conference in the bowels of the stadium, Billy and a cheerleader named Faison (Makenzie Leigh) make eye contact, and you just know something’s going to happen between them. At another point Billy, hanging out in the locker room, is surrounded by Dallas players and peppered with questions about combat and guns. Lee also effectively plays around with sight and sound, sometimes letting the volume fade away, sometimes having the color drain to black and white.

In the end, the war scenes are the highlights. But the stuff at the stadium just doesn’t ring true. As with the book, it takes up most of the film’s time. As with the book, it should have taken up less.

— Ed Symkus covers movies for More Content Now.

“Billy Lynn’s Long Halftime Walk”
Written by Jean-Christophe Castelli; directed by Ang Lee
With Joe Alwyn, Kristen Stewart, Chris Tucker, Garrett Hedlund, Steve Martin, Vin Diesel
Rated R