Amber Heard; Elon Musk.Photo: Neilson Barnard/Getty; Pascal Le Segretain/Getty

Amber Heard, Elon Musk

Elon MuskandAmber Heardrecall details about their relationship in Walter Isaacson’s new biographyElon Musk.

In the book, out Tuesday, the SpaceX founder and Tesla CEO, 52, and theAquaman and The Lost Kingdomactress, 37, open up about their romance, with which they went official in April 2017. The pair dated on and off in the months that followed, before breaking up for good in 2018.

Isaacson writesof their relationshipin the biography’s “Rocky Relationships” chapter that Musk first took an interest in the actress after seeing her in 2013’sMachete Kills, and that they met when she visited SpaceX a year later.

“I guess I could be called a geek for someone who can also be called a hot chick,” Heard said in the book, while Isaacson claimed Musk took her for a ride in a Tesla during that SpaceX visit.

Among other tidbits about their dynamic, Isaacson said Musk flew to Australia in April 2017 to visit Heard while she was filmingAquaman, and that she once commissioned a costume to “roleplay” a character Musk said she reminded him of: Mercy, from the video gameOverwatch.

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Amber Heard and Elon Musk in Sydney in May 2017.Media-Mode/Splash News

Amber Heard and Elon Musk

Isaacson also gets into some of the more tumultuous moments of Heard and Musk’s time together, including a fight they had near the end of their relationship while onvacation in South Americain December 2017 with family, including his brotherKimbal Musk.

While Heard allegedly admitted to Isaacson that the argument occurred, she also shared photos and videos of their evening afterward with him, which Isaacson said depicted the actress and tech mogul sharing aNew Year’s Evekiss.

Of their relationship, Musk said in the biography, “It was brutal.” For her part, Heard told Isaacson that she still loves her ex “very much,” and added: “Elon loves fire, and sometimes it burns him.”

Amber Heard; Elon Musk.Craig Barritt/Getty; JIM WATSON/AFP via Getty

amber heard, elon musk

Kimbal, 50, told Isaacson in the book that he thinks it’s “really sad” his brother “falls in love with these people who are really mean to him.”

“They’re beautiful, no question, but they have a very dark side and Elon knows that they’re toxic,” he continued.

A rep for Heard did not immediately respond to PEOPLE’s request for comment on Monday.

Over a year after the breakup, Heard toldThe Hollywood Reporterin December 2018, “Elon and Ihad a beautiful relationship, and we have a beautiful friendship now, one that was based on our core values. Intellectual curiosity, ideas and conversation, a shared love for science. We just bonded on a lot of things that speak to who I am on the inside. I have so much respect for him.”

Elon Musk, out Tuesday, isavailable for preorder now.

source: people.com