For Elon Musk, the US Justice Department’s release of 3 million additional files related to criminal investigations of Jeffrey Epstein last month was immediately embarrassing. Attention in particular fell on emails Musk sent the financier several years after he pleaded guilty to solicitation of prostitution and of procurement of minors to engage in prostitution in Florida and registered as a sex offender.

“What day/night will be the wildest party on your island?” Musk wrote in November 2012, for example, appearing to seek an invite to Little Saint James, Epstein’s private island in the Caribbean.

While there has been no confirmation that any such visit occurred, the messages contradict Musk’s longstanding insistence that he didn’t know Epstein well and had always rebuffed his overtures. Other files reveal that an associate of Musk’s spent weeks corresponding with Epstein behind the scenes of a major drama for Tesla and its embattled chief executive.

Musk did not return a request for comment.

A batch of emails reviewed by WIRED shows that in 2018, after Musk posted on social media that he was “considering taking Tesla private” in a move that never came to fruition, one of the CEO’s surrogates was sounding out Epstein for advice on financing the deal and potential board members for a reorganized Tesla. They also went back and forth over Musk’s leadership qualities.

Musk was having a difficult time in 2018, beset by challenges at his companies while his increasingly erratic behavior on social media seemed to take its toll on his public image. That June, as the world waited in suspense for the rescue of a Thai youth soccer team trapped in a submerged cave, he’d decided to involve himself. What he offered was a miniature submersible that he claimed ...