I Am: Celine Dion review – Moving and unsanitised look at life-changing diagnosis

Following a cancellation of her Las Vegas residency, Celine Dion shared that she had been diagnosed with a rare condition, Stiff Person Syndrome, in an emotional Instagram video. The autoimmune neurological disorder causes muscle stiffness and painful spasms, and can worsen over time.

And now the singer is ready to share a harrowing insight into her life with the condition.

Celebrity documentaries often fixate on finding new ways to tell stories, without really sharing anything. I Am: Celine Dion is different.

This isn't a film for someone who just wants to know more about the lady who sang the world-famous theme to the blockbuster Titanic film. Instead, the viewer is expected to know exactly who she is already – and there's little time for catching up.

It does nothing to introduce Celine or show her rise to stardom. Rather, it focuses on her as an established powerhouse, before instantly stripping it back to a woman at home in her pyjamas, counting out her medication.

It's also not a behind-the-scenes look at her best known, chart-topping songs; in fact, her musical repertoire is only featured in snippets to highlight her love of being on stage, and to show off the voice that's given her a reputation of producing incredible power ballads.

The true focus of I Am: Celine Dion is an honest portrayal of the life of a woman battling a condition that affects only one in a million people. She often appears make-up-free with her hair back as she shares her innermost thoughts, getting choked up as she talks about her pain and her struggle to walk.

There's a dual life that Celine is leading. Clips of her on talk shows, showing her dazzling personality, are cut with the singer at home, talking to her sons, feeding her dog and documenting the physical therapy she's undergoing in an attempt to get back on the stage.

She highlights all the people who have joined her on her journey, saving particular praise for her team, band and backing singers, explaining how they have become her family.

"If you want to go fast, go alone. If you want to go far, go together," she says poignantly.

Consequently, there's a lot the documentary doesn't feature. Her marriage to manager René Angélil, for example, is shown only briefly, mainly in fleeting montages of the couple welcoming their sons, and in glimpses of home movies. There's a momentary look at Celine and the couple's children at René's funeral, followed by her breaking down in tears as she performs All by Myself to thousands of adoring fans.

Emotion is a constant thread that runs throughout the one-hour and 42-minute long documentary. At one point, Celine explains how the spasms affect her, the muscles in her chest tightening in front of her lungs, and her throat spasming so she can't get her voice to reach the heights she craves. It's a powerful moment, as the crushing disappointment is etched across her face.

However, despite Celine's obvious torment at not being able to do what she loves, or have control of her ability, she never asks for sympathy.

She's everything you want from a pop star – funny, eccentric and says exactly what she thinks with no filter and finds any moment to burst into song.

She's somehow relatable, even after taking viewers through an entire warehouse of her clothes and shoes. And the shoes are extra special, with the singer declaring she will go to shops and ask them what sizes they have. "When a girl loves her shoes, she always makes them fit, from six to 10, give it to me," she says. All those traits are perfectly captured. As is the love she has for her three sons, René-Charles 'RC' Angélil and twins Eddy and Nelson.

The film ends showing the full extent of what Celine is dealing with, even when it makes for some raw, and somewhat uncomfortable, viewing. Following a recording session where she's disappointed in her ability, she notices she's having a foot spasm that doesn't go away.

The camera remains tight on her as she goes into full body spasm, unable to communicate as her team gather around her to protect her head and prepare her medication.

It's difficult to watch; it feels as if you are prying on a private moment as her weeping gets louder. When it passes, the exhausted singer shares her embarrassment, lamenting how awful it is to not have control of your own body.

Through it all, however, it’s the music – both her past success and future endeavours – that remain foremost in her mind. After being told her body is overstimulated from recording, she despairs over how she'll ever be able to perform live again. But music is also there to save Celine. Her team play a song for her, Who I Am by Wyn Starks, and she's instantly back to doing what she does best, singing and performing as only she can.

It shows her resilience. "If I can't run, I'll walk. If I can't walk, then I'll crawl."

From start to finish, the documentary shows someone at their most vulnerable. It is unsanitised, gritty and real – qualities that are not always easily found in other celebrity-led documentaries.

Taken as a whole, it is a must-watch. It's not just for the many millions of fans of Celine's music, but for anyone who wants a true-to-life portrayal of the daily, if not hourly, ups and downs of someone living with a debilitating condition.

When juxtaposed with Celine's authentic kindness and determination to fight, it makes for a moving, through-provoking, and oddly uplifting watch. It's not one to be missed.

I Am: Celine Dion will be available worldwide on Prime Video from Tuesday 25th June – try Amazon Prime Video for free for 30 days.

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