Michael J Fox on why he wants to tell his story in documentary preview

"My world is getting smaller," he responds when asked why now was the right time. "I love my mind and I love the places it takes me and I just don't want that to get cut short."

He is then asked if there might be a moment – perhaps 20 years from now – when he is no longer able to tell his story.

He responds: "Well if I'm here 20 years from now I'll either be cured or like a pickle." You can watch the clip in full below:

Speaking in the film's press notes Fox explained that although the disease is incurable, it "still doesn't scare me".

"When I was younger, I fought the idea," he said. "When the doctor first told me, I said, 'That isn’t going to happen to me.' Good things happened to me. But then this bad thing did. The first 10 years or so, I got locked in that place, a good place, by not allowing anyone else to define my reaction to it."

He added: "Parkinson’s didn’t just kick me out of the house; it burned the f**king house down. It went after me really hard. The way I dealt with it was not to pay attention to it.

"In the last three years, I broke both femurs. I had one shoulder replaced. I broke my face. I broke my hand. I broke a lot of stuff. I realised, I could die from this, which does freak me out. But I can deal with it if it comes up. My biggest fear is to become incurious."

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The film is directed by Oscar-winning director Davis Guggenheim, whose past work includes An Inconvenient Truth, Waiting for "Superman" and He Named Me Malala.

Its official synopsis reads: "A short kid from a Canadian army base becomes the international pop culture darling of the 1980s, only to find the course of his life altered by a stunning diagnosis.

"The actor who is an incurable optimist is forced to confront an incurable disease."

Still: A Michael J Fox Movie will be in select cinemas and streaming globally on Apple TV+ on Friday 12th May – you can sign up to Apple TV+ here.

Check out more of our Film coverage or visit our TV Guide and Streaming Guide to see what's on tonight.

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