Although filmmaker Stephen Kijak is known for his music documentaries including "Stones in Exile," "Backstreet Boys: Show ‘Em What You’re Made of" and "Jaco," a film about the late legendary jazz bassist Jaco Pastorius, he didn’t know what he was getting into when he was introduced to the Japanese metal band X.

"I had never heard of them before I got called by my producer to do the film, to be perfectly honest," Kijak said during a telephone call from Los Angeles. "It was a whole world of discovery for me, and as someone who has done a lot of films about music and musicians, I was deeply embarrassed to discover a massive gap in my knowledge."

Still, Kijak agreed to make the film, "We Are X," which is part of the Sundance Film Festival’s World Documentaries, and embarked on a one-and-a-half-year "mind-bending" journey.

What sold the filmmaker was the band’s slogan, "Psychedelic violence crime of visual shock."

"That was an immediate yes for me," he said with a laugh. "I thought whatever that was, I wanted a piece of it. I wanted to know what that was all about."

At first, Kijak was struck by the band’s look.

"Obviously the first impression of the band is visual when you see the hair, the makeup and the outrageous styles," he said. "Then I listened to the music, but I had no context, even when I looked up things on YouTube."

What caught Kijak’s ear was this classically-based, speedy, heavy, dramatic, over-the-top music that was mostly in Japanese with some English.

"I couldn’t believe that I hadn’t heard it before, but I wasn’t immediately drawn to it, to be perfectly honest," he said. "I had abandoned metal when I was 13 or 14 when I went new wave."

But the new wave connections helped him relate to the band, especially lead singer Toshi (Deyama) guitarist Sugizo (Sugihara Yuu), and the film’s main subject, drummer Yoshiki (Hayashi).

"It was interesting to learn that for most of them David Bowie, rest in peace, was their hero and that they also were inspired by punk and new wave," Kijak said. "When I met Sugizo, we had a long conversation about the band Japan and its bassist Mick Karn."

More connections emerged during their discussions.

"I mean, they are a little older than me, but not by much," Kijak said. "In fact, the first record Toshi, Yoshiki and myself ever bought was Kiss ‘Love Gun.’ So, we had more in common than I could imagine."

Still the learning curve was steep, especially because the film was being made during a time when X, also known as X Japan, was preparing for a reunion concert of sort at Madison Square Garden on Oct. 11, 2014.

"Meeting Yoshiki was really an inscrutable and enigmatic experience," Kijak said. "He has this soft-spoken quality and is strangely androgynous. And you get this sense that you’re in the presence of a Japanese rock god, which doesn’t happen every day."

The filmmaker also found Yoshiki to be completely mercurial, yet completely in charge of his whole world.

"There are these circles of chaos that swirl all around him that he seems to orchestrate perfectly to make things happen," Kijak said. "It was a real rush."

A week after the meeting, the filmmaker found himself in Yokohama, Japan, watching the band’s warm-up shows for Madison Square Garden (MSG).

"It was the moment when I saw the crowd do the ‘X Jump,’" he said. "We’re talking a sold-out, 18,000 or 19,000 people at the Yokohama arena with their Glo-sticks making all of these X symbols jumping in unison to this song, and I could not believe what I was witnessing. It was electric and it was an exciting experience, and I felt like I was transported to a parallel universe."

The film includes cameos by music critics, biographers and Marilyn Manson.

"It’s interesting because I think Manson and Yoshiki crossed paths after Yoshiki was doing his band Violet UK and did a fashion event in Tokyo that Manson was a part of," Kijak said. "I think Manson got to know Yoshiki apart from the band, but as a creative person and they formed a friendship."

Kijak said Yoshiki is someone Manson could relate to.

"Manson fully admits his persona is a character that he’s created, much in the same way Yoshiki puts on different aliases and visual personas he takes on," he said.

Director David Lynch is also in the film by pure accident.

"Yoshiko and Lynch collaborated a long time ago," Kijak said. "Lynch was getting ready to do ‘Lost Highway’ and Yoshiki commissioned him to do a music video for the song, ‘Longing.’"

Kijak found the footage while rummaging through Yoshiki’s boxes of video archives.

"Most of it was labeled, but some of the videos were pure mystery," he said with a laugh. "I pulled them out and looked at them and found all of this behind-the-scene footage of that shoot and there was David Lynch with a megaphone directing Yoshiki, standing in the middle of the desert with flames shooting up around him.

"I went, ‘Oh, this has got to go in the movie,’" Kijak said. "It wasn’t like we interviewed Lynch. He just appeared in an archive. You don’t ignore those kind of coincidences."

Finding the connection with Lynch drew Kijak further into Yoshiki’s world.

"Lynch is one of my biggest influences cinematically, and to have those connections come together by chance is incredible," he said.

"We Are X" is different than Kijak’s other films because of its style.

"There is a surreal and dreamlike quality of the documentary," he said. "It starts off like a traditional rock doc, but we immediately take a turn and try to dive deeper under the surface psychologically and emotionally.

"It’s about X Japan, but a portrait of Yoshiki, which is something he doesn’t allow the world to see very often," Kijak said. "I will say the biggest challenge was editorial. You have an enormous story with many characters, albums, drama, and you also have a portrait of one man and his life’s work. The challenge was to balance those two things and create something that has integrity and authenticity."

Sundance Film Festival will premiere the world documentary "We Are X" at the Prospector Square Theatre, 2200 Sidewinder Dr., on Saturday, Jan. 23, at 2:30 p.m. Additional screenings will be held at the Tower Theatre in Salt Lake City on Sunday, Jan. 24, at 6 p.m.; the Redstone Cinema 2, 6030 Market Street, on Tuesday, Jan. 26, at 10 p.m.; the Yarrow Hotel Theatre, 1800 Park Ave., on Thursday, Jan. 28, at 9 a.m. and the Holiday Village Cinema, 1776 Park Ave., on Friday, Jan. 29, at 9:15 p.m. For more information, visit http://www.sundance.org.