Metallica drummer Lars Ulrich has given film crews permission to shoot intensely personal band therapy sessions, been shot in the shower by group’s main photographer and played a major role in the creation of the band’s most ambitious, but least enjoyable albums, ‘St. Anger.’

Yet, he told Newsweek recently that his favorite mistake was not giving movie director Quentin Tarantino permission to use the Metallica songs ‘Enter Sandman’ and “Sad But True’ in two of the main fight sequences in ‘Kill Bill.’

The request from Tarantino came during an animated dinner the director had set up with Ulrich. During the meal, Tarantino described how he wanted to use the songs to mirror the on screen action.

“Fists would impact faces on accents. Kicks would land on cymbal hits. Bodies would twirl along with the rhythm of the music,” Ulrich says. “[It would have been] Tarantino’s next-level movie magic married to Metallica music, all turned up to 11.”

At first, Ulrich was stoked about the idea. Then the script arrived in the mail and as he read the copy, he became more and more perplexed by “language, twists, turns, kung fu banter and jargon.” Gradually, the idea he was once so excited about didn’t seem so appealing.

“I realized that most of this was written in a language that was outside of my realm of understanding,” he said. “I just couldn’t wrap my thick Danish head around it. I championed his movies, loved him as a person, but at the end of the 180 pages, I sat there somewhat bewildered and felt very uncool for not getting it.”

In the end, Ulrich didn’t get back to Tarantino and the idea was dropped. To date, Ulrich considers his ultimate dismissal of the project “the single biggest mistake I’ve made in the creative department.”