Céline Dion's New Doc Shows Heartbreaking Footage of Singer Experiencing a 10-Minute Seizure

'I Am: Celine Dion' shows how life has changed for the 56-year-old singer since her diagnosis with Stiff Person Syndrome.

Céline Dion is showing all the toughest moments in her battle with Stiff Person Syndrome (SPS).

In her new documentary, I Am: Celine Dion, the GRAMMY winner is seen during moments of immense pain, and even a startling seizure which lasts for several minutes,

"I don't know how to express it, like, it's just … you know, like, to not have control of yourself?" she tells the cameras.

In December 2022, Dion revealed that -- after months of struggling with heath issues, including muscle spasms and stiffness -- she had officially been diagnosed with SPS, a rare autoimmune disorder.  

According to the Mayo Clinic, Stiff Person Syndrome is "a rare disorder of motor function characterized by involuntary stiffness of axial muscles and superimposed painful muscle spasms, which are often induced by startle or emotional stimuli."

I Am: Celine Dion doesn't shy away from showing Dion's new reality with her illness, as she strives to live and perform like usual, but is occasionally sidelined by scary seizures. 

During one moment in the doc, the 56-year-old singer is paralyzed for several minutes as she suffers a full-body seizure after a medical evaluation.

"Part of the disease is that as soon as you go into a contraction, sometimes … the signal to release it, doesn’t understand, so it ends up just staying in a contracted position,” explains sports medicine therapist Terrill Lobo.

The medical team treats Dion with Valium and nasal spray, but when her symptoms persist and even get worse, they have to consider taking her to the hospital as it can lead to a "crisis."

Paralyzed but sobbing, Dion signals to one of the medical team members by squeezing their hand until she is able to move again. When she regains her bodily functions, the singer tells her team that she feel "so embarrassed" by incidents like that.

Céline Dion first announced her SPS diagnosis in December 2022. - NBC

Since announcing her SPS diagnosis, Dion has been open with fans about how the condition has affected her life and career -- and effusive in her thanks for their support every step of the way.

She was forced to cancel her Courage World Tour, which restarted in 2022 after being paused due to COVID, but she has made several public appearances in recent months, including a surprise onstage moment at the 2024 GRAMMYs and several trips to hockey games with her sons.

Earlier this month, prior to the documentary premiere, Dion sat down with Today's Hoda Kotb for an interview about her condition, getting candid on camera about the trials she's faced since her diagnosis.

The singer shared that, for her, Stiff Person Syndrome first presented itself in her throat -- locking up the muscles in a way that made it feel "like somebody is strangling you" when she tried to sing. It has also caused spasms in her abdomen, spine, ribs and limbs, with Dion noting that the ailment can manifest itself by locking her limbs in certain positions, for example, when cooking or pointing her toes. 

The spasms have even gotten so bad, on occasion, that the singer has suffered from broken ribs. But perhaps an even greater pain for the singer came from keeping her condition a secret. Dion told Kotb she felt she was "lying to the people who got me where I am today," adding that there came a time when "I could not do it anymore."

"I should have stopped, take the time to figure it out," she lamented. "I had to raise my kids. I had to hide. I had to try to be a hero. Feeling my body leaving me, holding onto my own dreams. And the lying for me was - the burden was like too much."

I Am: Celine Dion is streaming now on Prime Video.