Shia LaBeouf, 26, who is quickly fostering a reputation as a notorious Hollywood bad boy, is explaining how he came to bare all in June of this year in a music video for the Icelandic band, Sigur Ros. "I wrote a fan letter," LaBeouf said of his nudity in the Alma Har'el-directed video for the song, "Fjogur piano."

"I saw Bombay Beach, the movie that Alma Har'el made," LaBeouf told Vulture at the premiere of his new Lawless, a film about bootlegging during prohibition, costarring Tom Hardy, Gary Oldman, Guy Pearce, Jessica Chastain, Mia Wasikowska and Dane DeHaan — a role for which LaBeouf reportedly packed on fifty lbs.

"It touched me. I told her so. She told me she'd like to work with me. I said, 'What are you doing?' She said, 'I got this Sigur Ros thing.' I said, 'Cool. Can I get involved?'"

The resulting project, which evolved as LaBeouf worked with Har'el, depicts a couple in a tumultuous, at times psychedelic, relationship, making love and fighting interchangeably. "Well, we were playing a couple in the midst of a drug-addled binge," said LaBeouf.

"It was extremely abusive. And the direction from Alma was: 'You two wake up in bed after having made love all night, and now starts the bad site of this.'" The actress in the video was nude, leading LaBeouf to reason, "There's no way I would have slept with you in my clothes and gotten up with my clothes on and come to this moment. If you're going to be naked, I should be naked as well," he said.

Lawless hits theaters on August 29.

Watch the video for Sigur Ros' "Fjogur piano," directed by Har'el, here:

For more on Shia LaBeouf:

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