He’s the “Rhinestone Cowboy,” a Grammy winner, a country superstar, a TV show host, and now, thanks to his new documentary, I’ll Be Me, Glen Campbell is the spokesman for a disease that currently affects more than 5 million Americans.

Alzheimer’s is a diagnosis no one wants to receive, but in 2011, Campbell and his family announced to the world that the famed country crooner was in fact suffering with the debilitating disease. Faced with the prospect of losing basic motor functions, memory recall, language abilities and more, Campbell made a choice few would even have the courage to consider; he decided to go on tour and in front of the camera.

In what began as a 151 stop farewell tour to his millions of fans, Campbell’s musical road trip soon grew into a movement. Thanks to director James Keach, who suggested the family film their experiences on the road, Campbell was able to do something thousands of non profits, politicians and activists had yet to accomplish: give a raw and unfiltered glimpse into one of our nation’s worst epidemics.

Narrated by his wife Kim, I’ll Be Me is a poignant, often tear-inducing account of Campbell’s journey with Alzheimer’s. From early diagnosis to the crippling later stages, the disease completely consumes the singer’s life, but it never manages to erase Campbell’s most notable attribute: his musical talent.

A year and a half of touring, performances in front of law makers at Capitol Hill, a Lifetime Achievement Award at the Grammys, countless shows, thousands of fans and endless hours in hotels and on buses are all documented in the new movie. We see Campbell’s bond with his family as Kim becomes his primary caretaker and shows the patience and compassion necessary to deal with some of the darker sides of the disease — paranoia, anger, memory loss and more begin to take their toll on the artist towards the end of the tour.

Campbell’s children also play a role in the film. His sons Shannon and Cal along with daughter Ashley all join their dad on stage, coaching him along when he forgets lyrics or becomes a bit unruly at rehearsals. At one point in the film, Ashley riffs with her dad during a set, proving that the musician’s God-given talent hasn’t completely been taken by his disease, but it’s her speech to senators in Washington, D.C. that shows what Alzheimer’s has really taken away, not only from her father but from her family as well.

“I think a person’s life is comprised of memories, and that’s exactly what this disease takes away from you,” Ashley can be seen saying in the film, “Now when I play banjo with my dad, it’s getting harder for him to follow along and it’s getting harder for him to recall my name. It’s hard to come to the realization that someday my dad might look at me and I will be absolutely nothing to him.”

It’s the recording of what became Campbell’s final song that probably sums things up the best. With friends from the famed Wrecking Crew, Campbell shares a tender farewell to his wife Kim with “I’m Not Gonna Miss You.” The track shows the artist’s awareness of his own decline but it’s the clips of moments shared with loved ones, friends, fellow artists and on the stage that really give weight to the lyrics.

I’ll Be Me won’t be easy to watch. Campbell — beloved by fans — transforms from a talented jokester with a love for life and sharp wit to a man who needs help with the simplest of tasks and often can’t remember who he is. But through it all, he never loses his ability to riff a guitar, belt out a popular tune, and or belive in God and what’s He’s called him to do.

I’ll Be Me is out in theaters Oct. 24th.