Following Tuesday night’s premiere of the brutally frank new Steve Gleason documentary, Saints coach Sean Payton addressed the audience at New Orleans’ Orpheum Theater. Seeing “Gleason” for the first time, he confessed, had left him a little choked up and struggling for words.

At which point Gleason himself, parked nearby in his high-tech wheelchair, interrupted with a synthesized voice and perfect comedic timing: “What a wussy.”

But he didn’t use “wussy.”

The audience erupted in laughter. Payton, caught off guard, paused, smiled and agreed.

Even though he is completely paralyzed and has endured innumerable hardships since being diagnosed with the devastating neuromuscular disease ALS in 2011, Gleason’s unfettered, unfiltered and unselfconscious sense of humor and mischief remain.

That is apparent throughout “Gleason,” which opens nationally on July 29.

Across four years of his ordeal, a camera crew embedded with Gleason and his family shot 1,300 hours of footage. Director Clay Tweel also used video diaries Gleason recorded for his son, Rivers, who is now 4. Knowing that he would eventually lose the ability to speak, Gleason sought to share as much of himself with Rivers as possible.

In “Gleason,” he shares a whole lot more. It is an hour-and-45-minute reality show that documents, in unflinching, intimate detail, a very difficult reality, one that turns on a twist of fate that is Shakespearean in its cruelty.

Prior to Tuesday’s screening, Drew Brees warned those in attendance – including current and former Saints players – that there wouldn’t be a dry eye in the house. He was correct.

“Gleason” whips from raw to humorous. Through it all, his positive attitude, though severely tested, is critical to his survival.

Determination and drive were there from the beginning. His parents fought constantly and eventually divorced. Steve took out his anger on the football field, his speed and aggression compensating for his lack of size. Through seven seasons with the Saints, he tackled with kamikaze abandon.

His most famous play — blocking an Atlanta Falcons punt during the first game in the Superdome after Hurricane Katrina — is covered, briefly, early in the film. This story is about much more than football.

Upon first meeting Gleason, a long-haired NFL player who drove a truck, the free-spirited Michel Varisco “thought he was going to be a complete cheeseball.”

But they clicked. They traveled the world. They got married. The officiant, in his remarks, asks, “How do we act when things aren’t great? When things are difficult?”

The couple had no idea just how difficult things would become.

Barely two years into their marriage, Steve started experiencing muscle spasms and other worrisome symptoms. In a video, he says the “worst-case scenario” would be ALS, also known as Lou Gehrig’s disease.

Confronted with that worst case, he seeks to rise above his diagnosis: “It’s not going to crush my life, even if it does crush my body.”

Six weeks later, he and Michel learn she is pregnant.

Four months after the diagnosis, tears streak Michel’s face as her husband, once an elite athlete, struggles to swim across Bayou St. John with friends, who must help him climb onto the bank. The downward spiral has begun.

“I am sure there are people who get this diagnosis and shut down,” Gleason says. “It has ignited a fire in me.”

Cameras follow as Steve and Michel attend a faith healing at the behest of Steve’s father. Steve, who is already limping badly, attempts to run in front of the congregation. He crashes to the floor, face-first.

He returns to the Superdome to lead the Saints’ pre-game “Who Dat” cheer. He must steady himself by holding Brees’ arm as they walk off the field.

The impending arrival of Rivers provides some much-needed joy. Michel’s stunned, wide-eyed silence as she sits in the hospital, contemplating what her body is about to do, is funny. The birth scene itself is heavy; Steve assists in the delivery.

By early 2012, he is preparing for the inevitable. He practices the eye-tracking technology that will allow him to “talk” via computer. He records long passages of himself reading, so the synthesized voice will sound like his own.

“At this point it looks like we’re not going to have a normal father-son relationship,” he says to Rivers in a video journal. “It’s not going to be easy, but it’s going to be awesome.”

Soon Michel is feeding baby Rivers with one hand and her husband with the other. A family friend, Blair Casey, becomes Steve’s full-time caregiver, handling everything from lifting him in and out of bed to scratching his nose.

As Steve’s voice deteriorates, his slurred speech is clarified by subtitles. In one difficult scene, he weeps and wails uncontrollably. “I have no faith that I can heal. I have no hope… I want to punch something, but I can’t.”

He would regain hope. His Team Gleason charity would improve the lives of ALS sufferers. As the national face of the disease, he is a “hero” who struggles to control his bowels, all part of the “polarities, dichotomies and juxtapositions that are my life.”

The constant demands of caring for a toddler and a paralyzed husband wear Michel down. By 2014, Gleason is in danger of dying because he can no longer clear his lungs of mucus. He undergoes tracheotomy surgery to allow a ventilator to breathe for him. The procedure stabilized him, but there is no turning back.

Doctors initially gave him a maximum of five years to live. He surpassed that milestone in early 2016.

“People say it’s such a sad and tragic story,” he says at one point in the film. “It is sad, but it’s not all sad. I think there is more in my future than in my past.”

The strength, determination, love and humor on display in “Gleason” demonstrate why.

Follow Keith Spera on Twitter, @KeithSpera.