HEARTBREAK BEHIND HIS BOOK DEAL!

Chris wants to immortalise his legacy for his children

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After 10 years in showbiz, Chris Hemsworth won the hearts of people all over the world last year when he revealed he was stepping away from acting to spend more time with his children.

And while at the time, Chris, 40, said his decision wasn't linked to the shock discovery he made while filming Limitless that his chances of developing Alzheimer's disease were eight to 10 times higher than most, insiders say filming the series has changed his mindset - and inspired him to write a memoir.

Chris found out during gene testing for the show that due to inheriting copies of APOE4 from both his mother and father, he had an increased risk.

PUTTING PEN TO PAPER

"Chris started jotting down ideas for his book after his 40th last August, but things weren't that serious until last week, when he hired one of LA's top literary agents," says the source.