Paul-Henri Nargeolet's friend said he has 'recurring nightmarish' thoughts about the explorer dying on the Titanic submersible and wanted to gift him leather Uggs to protect his 'frozen' feet

• A friend of a man who died on the Titanic sub has "nightmarish thoughts" about the explorer.
• He told People that he had hoped to gift Paul-Henri Nargeolet a pair of Uggs for the expedition.

A friend of Paul-Henri Nargeolet — a deep-sea explorer who tragically died on the Titan submersible — told People he's been having dark thoughts about his friend's death on board the vessel.

Fred Hagen, who previously worked as a mission specialist on the Titan, told People he has had "recurring nightmarish" thoughts about he could have helped his friend, specifically how to stay warm while he was possibly stuck thousands of feet deep in the ocean, where temperatures are below freezing.

He said he had wanted to gift Nargeolet, who has been to the Titanic shipwreck over 35 times and is known as "Mr. Titanic," a pair of leather Ugg boots like the ones the explorer wore during his first plunge to the site, but told People that he "never got around to it."

"He's suffering, he may be dying, and his feet are probably frozen," Hagen said he was thinking when the world was unsure whether the passengers stuck on the sub were alive.

"And if I had just ... made the effort to get to send those Uggs to him like I intended then he wouldn't have had to die with frozen feet," Hagen said.

Ultimately, following a four-day search that commenced once the sub lost contact with its mother ship under two hours after it set out on its mission, it was determined that the vessel had imploded and that all of the passengers had died from the incident.