Oscar nominee Irene Taylor says she "panicked" a bit when she was asked to make a documentary on a celebrity as popular as Celine Dion, but she agreed to come on board after she got to know the singer personally.

"I Am: Celine Dion", a 1.42 hour-long documentary, is a moving portrait about the era-defining musician braving a rare autoimmune neurological disorder called the Stiff-Person Syndrome (SPS). It started streaming on Prime Video from Tuesday.

The filmmaker said it wasn't until she developed a fondness for Dion that she decided to direct the film. Taylor is best known for Academy Award-nominated "The Final Inch", about the global effort to eradicate polio, and "Hear and Now", a documentary memoir following her deaf parents as they receive a complex implant surgery.

"Part of me was panicked because I had never made a film about a celebrity before. I had never had a really strong motivation to do that. I thought 'What am I going to do? Just go on tour with her? Is that interesting? I don't really know'.

"But, I knew I really liked her because I had got to know her and I got the sense that she would be authentic with me. So, I agreed to get on board and make the film," Taylor told PTI in an interview.

According to the makers, "I Am: Celine Dion" is a raw and honest behind-the-scenes look at the iconic superstar's struggle with the life-altering illness which has affected her singing.

Dion, the voice behind powerful ballads "My Heart Will Go On", "That's The Way It Is", "The Power of Love", and "I'm Alive", was already unwell when she started filming for the documentary. And this was something the singer and her management team shared with Taylor just before they started shooting.

"Shortly before we started filming, her management and Celine herself confided in me that she was ill. They didn't know what the problem was but they were in the process of getting to the bottom of it.

"When I was told that it had become much more clear that I'm not going to go on tour with her. I might, but if I do, she'll be sick. The film is not just about the illness, it's about many other things. But I knew that would give me focus," she added.

Something shifted in the Las Vegas-based singer when she announced her diagnosis in a social media post in December 2022, the director recalled.

In a tearful video on Instagram, Dion had told fans and followers that she was suffering from SPS and cancelled her European tour set for February 2023.

"I saw something shift in Celine when she made that Instagram post that came out... a year and a half ago. When we were shooting the film, there is what I call the before Instagram post era and after Instagram post era," Taylor added.

The 56-year-old singer, the filmmaker said, made the revelation on social media because she was "consumed with guilt of lying".

"She felt like she was lying. Now, that is a very strong word and you could debate whether that is the right word to use or not but what happened was she felt so much lighter.

"She says in the film 'The lie is too heavy now'. When she told the world, then she was elevated. But a lot happened in her life and in the film after she made that post. So, we weren't done." For Taylor, "I Am: Celine Dion" gradually became an experience about a woman she was getting to know and sharing it with the audience.

"She did not present (herself) like 'Celine Dion'. She presented (herself) as a woman named Celine who grew up in French Canada and now lives in Las Vegas with her children.

"She has habits, she likes to vacuum, and she makes her own coffee, she cooks her own food. She was just a person I felt I could relate to. So, I just really tried to share with my audience the woman I was getting to know," she said.

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