Tesla board member and close Musk confidant Antonio Gracias once took Musk's phone away to prevent him from tweeting late into the night, Isaacson said during a Twitter Spaces event on Wednesday.
"At one point when Elon was firing off tweets without filtering them in the least, they were on a trip and Antonio took his iPhone — Elon's iPhone — and locked it in the hotel safe with Antonio punching in the code so that Elon couldn't get up at 3 a.m. and start tweeting again," Isaacson said, describing Gracias as "one of Elon's closest friends."
Musk later got hotel security to open the safe at around 3 a.m. so he could start tweeting again, Isaacson said.
The biographer added that Musk is "almost addicted to the drama that comes with Twitter" and sees owning Twitter as a way he can be "king of the playground."
"It's something he loves — loves almost to the point of compulsion," Isaacson said, adding that some of his friends, including his brother Kimbal Musk, attempted to convince him not to buy Twitter.