One of the many blessings of the Ice Bucket Challenge craze that swept the globe in 2014 was that it made people aware of ALS, a brutal disease that robs a person of his or her ability to walk, talk, and eventually, breathe. Prior to the Ice Bucket Challenge, most people only knew about ALS if a friend or family member had been diagnosed with it.

The great news is that those donations are already having an impact on the research. The ALS Association spent some of the Ice Bucket Challenge donations on Project MinE, which just announced on Monday that it had discovered a new ALS gene, one that is among the most common among people who have familial ALS.

While the Ice Bucket Challenge raised great awareness about ALS and the need for greater funding for research and care services, many people still don’t know what exactly ALS is or how it affects a person. Fortunately, former NFL player Steve Gleason has documented his journey and is sharing it in a new documentary that opens this weekend. The Daily Beast has called it “the most powerful, poignant documentary of the year.”

I was fortunate to see an early screening and I can say that Gleason is raw, honest, and uncompromising. It’s not just about the physical toll that this horrible disease takes on a person, though there is certainly plenty of that. It also shows the emotional toll the disease takes on everyone, especially the person living with ALS and his or her immediate family members.

But Gleason also demands something of the viewer. It is virtually impossible to view the movie without becoming engaged, without tapping deep into one’s own self. At a screening in DC, many viewers were deeply affected, some even needed consoling. I, myself, literally had to leave the theater at one point because of how the movie triggered my own grief over some personal losses.

Given all this, you may be tempted to think the movie is heavy. And it is. But it is also filled with joy and humor and grace. It’s deeply rewarding and highly entertaining. The truth is, given how perfectly this film captures the human experience, everyone should see it.

Over the last two years, I’ve come to know many people with ALS. I have never met a more inspiring group of people. Despite the death sentence they’ve been given, these folks fight to raise awareness for ALS, to raise money for research, and to improve health care, among their many fights. All the while, they are fighting against their own bodies, which are shutting down on them. Gleason is as close to a sense of what ALS is – and how it can bring out the best in people – as I’ve ever seen.

You may not know someone with ALS. But after watching Gleason, you will. And if you’re like me, you’ll thank Steve Gleason and all those folks bravely fighting ALS for making their fights public and showing the rest of us what real courage looks like.

To see the trailer and find out where you can see Gleason, click here.

Brian Frederick is Executive Vice President of Communications & Development at The ALS Association.