At the climactic moment in the climactic game near the end of the 1979 film North Dallas Forty, Delma Huddle, having reluctantly let the team doctor shoot up his damaged hamstring, starts upfield after catching a pass, then suddenly pulls up lame and gets obliterated by a linebacker moving at full speed. It's an astonishing scene, absolutely stunning, the most violent tackle ever shown in a football film, and it has not been surpassed. Fans at the time had never seen the violence of football up so close. I played professional football, but I was stunned by the violence of the collision. It did not seem fake. It felt more real than the reality I knew. Despite my usually faulty memory, that scene has stayed in my head for more than 30 years.

The movie was based on a book by the same name, written by Peter Gent (he collaborated on the screenplay). Gent died Sept. 30 at the age of 69 from pulmonary disease. In North Dallas Forty, he left behind a good novel and better movie that, like that tackle scene, resonates powerfully today in ways he could not have anticipated.

A basketball, not football, player from Michigan State, Gent played wide receiver for the Dallas Cowboys from 1964 through 1968, then was traded and cut, and started writing a novel. Published in 1973, North Dallas Forty was a fictional contribution to the radical critique of pro football memoirs being written by Dave Meggyesy, Bernie Parrish, Johnny Sample, and Chip Oliver. Gent exaggerated pro football's dark side by compressing a season's or career's worth of darkness into eight days in the life of his hero, Phil Elliott. Except for a couple of minor characters, Elliott is the only decent and principled man among the animals, cretins, cynics, and hypocrites who make up the North Dallas Bulls football team and organization. The parlor game when the novel first appeared was to match fictional Bulls to actual Cowboys. Seth Maxwell, the down-home country quarterback and Phil's dope-smoking buddy, was obviously based on Don Meredith. So, did that mean that Meredith was a dope-head? How close was the ruthlessly self-righteous head coach to Tom Landry? And what about the wild linemen, Jo Bob and O. W.—did they have real-life counterparts? But Gent had larger aims. Writing a quintessential 1960s novel, Gent shared the apocalyptic vision of writers such as Vonnegut, DeLillo, Pynchon, and Mailer. Violent and dehumanizing, pro football in North Dallas Forty reproduces the violence and inhumanity of what Elliott calls "the technomilitary complex that was trying to be America."

I was in what proved to be my final season with the Kansas City Chiefs when Gent's novel appeared. The football world he described wasn't mine. I had come to terms with playing football while opposing the war in Vietnam back in college at Notre Dame. I lived a double life, half of the year a bearded graduate student at Stanford, the other half a clean-shaven member of the Kansas City Chiefs. I didn't recognize my teammates in his North Dallas Bulls. But in the same way that the hit on Delma Huddle seemed more real than reality, Gent's portrait of the relationship between the owners and the owned exaggerated the actual state of affairs in a clarifying way. At key moments with the Chiefs, I truly felt "owned," and the 1973 season proved to be my last because I was cut at the end of the players' strike during training camp in 1974. We struck over "freedom issues," like the one-sidedness of contracts and the absolute power of the commissioner, for which we were accused by the public of being "greedy" and by the owners of threatening the survival of the game. Of course, the freedoms we failed to gain in 1974 are enjoyed by every NFL player today, and the NFL is doing just fine.

North Dallas Forty is excessive, melodramatic, and one-sided. As such, it belongs to the mainstream of football fiction written since the early 1900s. Football always seemed larger than life—that was the primary source of its appeal—and football writing always tended toward extremes of melodrama and burlesque rather than the lyrical realism and understated humor of baseball writing. Consistent with this tradition of football writing, the "truth" of North Dallas Forty lay in its broad strokes rather than particular observations. The characters weren't "real," but collectively they conveyed the brutality, racism, sexism, drug abuse, and callousness that were part of professional football—just a part, but the part that the public rarely saw and preferred not to acknowledge at all.

The movie is a milestone in the history of football films. It was the first football movie in which the games looked like real football (rather than the usual odd mix of newsreel footage from actual games and ineptly staged shots of the actors in "action"). The influence of NFL Films is evident—tight close-ups, slow motion, the editing for dramatic effect that by then the Sabols had taught everyone who filmed football games. The actors (with the exception of NFL players like John Matuszak in the major role of O. W.) were not wholly convincing as football players. That's always a problem. But the action seemed more real than staged, and there's that one stunning scene that's still stunning after more than 30 years of amped-up, digitally enhanced movie violence.

Gent's script follows his novel closely, with a slight change at the beginning and a large one at the end, both of them significant. The novel opens on Monday with back-to-back violent orgies, first an off-day hunting trip where huge, well-armed animals, Phil's teammates O. W. and Jo Bob, destroy small, unarmed animals in the woods, then a party afterward where the large animals inflict slightly less destructive violence on the females of their own species. On Tuesday, Chapter 2, Phil awakens to the pain and stiffness left over from Sunday's game. The movie flips the two scenes. In one of the great openings in American film, a very unathletic-looking and physically vulnerable Nick Nolte awakens, groaning, on Monday morning, and stumbles to the bathroom where he pulls some clotted material from his nose and slowly inventories the damage to his limbs and joints. Suddenly, Jo Bob and O. W. burst in with shotguns blazing, and the novel's opening scenes proceed to play out. The scenes are the same, then, but the reversal of order makes a difference. The novel is more about out-of-control American violence. The movie is more about the pain and damage that players like Phil Elliott endure in order to play football. The novel is darker, a long gaze into the abyss. Hollywood had to humanize it, but Gent gave them the material to make it human without sentimentality or macho stoicism, Hollywood's usual ways to handle pain and suffering.

The endings are more dramatically different. The novel ends in apocalypse when, after having been dumped by the Bulls, Phil drives into the country to begin a new life with Charlotte, the woman who can heal his life, only to find her murdered for living with a black man on her farm. The movie ends with Phil leaving the Bulls' corporate offices and bumping into Seth who, as always, knows everything that's happened and has taken care to protect himself. Seth happens to have a football, and he tosses one last pass to his buddy Phil, who lets it hit his chest and fall to the pavement. He's done. He's walking away. Presumably to Charlotte and a new life.

When I first saw the movie, I preferred the feel-good Hollywood ending to the novel's bleak one, because it was actually more realistic. Players do leave football for other lives, as Gent and Meggyesy and I did. But watching the movie again recently, I was struck by the fact that Phil's sense of utter freedom now seems an illusion. Charlotte may be waiting for him, but so perhaps are hip and knee replacements, back surgeries, depression, uncontrollable rages, maybe dementia. The movie powerfully and movingly portrays the pain from playing football, but at the time it was made, we were collectively unaware of the likely greater pain from having played it.

North Dallas Forty is something of a period piece in other ways, too. Players have not been so thoroughly owned since they won free agency in 1993. Surveillance of players' off-field behavior is no longer in the hands of private detectives but of anyone with a cell phone. But the experience of playing professional football—the pain and fear, but also the exhilaration-that is at the heart of North Dallas Forty rings as true today, for all the story's excesses, as it did in the 1970s. Peter Gent knew them firsthand and translated them into enduring art.

Michael Oriard is a professor of English and associate dean at Oregon State University, and the author of several books on football, including Bowled Over: Big-Time College Football from the Sixties to the BCS Era, just published by the University of North Carolina Press. He played football at Notre Dame in the late 1960s and for the Kansas City Chiefs in the early 1970s.