As The Batman promotional cycle continues to roll out, we have another music-related tidbit to keep us entertained. As you’ve probably already seen, the first preview clip of The Batman, starring Robert Pattinson as the Caped Crusader, was set to a version of Nirvana’s “Something In The Way,” and director Matt Reeves has said that his version of the Bruce Wayne character was inspired by Kurt Cobain. Now, in an interview with GQ, Pattinson has revealed that he actually made “ambient electronic” music in his downtime in an on-set tent during production.

Here’s the passage:

The set, on the outskirts of London, manifested as a “bubble within a bubble,” [Pattinson] says. “And the nature of the shoot was so kind of insular, always shooting at night, just really dark all the time, and I felt very much alone. Even just being in the suit all the time. You’re not really allowed out of the studio with the suit on, so I barely knew what was going on at all outside.” They built him a little tent off to the side of the set where he could go to decompress. And mostly he would pass the time getting weird in the bat suit. “I’d be in the tent just making ambient electronic music in the suit, looking over the cowl. There’s something about the construction of the cowl that makes it very difficult to read books, so you have to kind of almost lean forward to see out of the cowl.”

For the record, “the cowl” means the Bat mask.

Read the full feature here.

The Batman hits theaters on 3/4.