Metallica lead guitarist Kirk Hammett's solo EP Portals, a cinematic journey of expansive instrumental music out in time for this year's Record Store Day (April 23), is already a historic Metallica item. Not only is it the musician's debut solo effort and the first-ever solo project from any Metallica member while actively in the influential heavy metal band, but it probably wouldn't have come together at all until now.

Longtime Metallica fans can probably guess why, since roughly 20 years ago, a Metallica member attempting to market a side project resulted in the parties parting ways; their 2004 documentary Some Kind of Monster captures the fallout. Bassist Jason Newsted's band Echobrain hasn't been active now for several years, but his involvement in that project back then created the rift that would lead to his departure from Metallica.

These days, things are much different in the Metallica camp, as Hammett explained to Loudwire in an exclusive interview. But that's not the only reason he hasn't released a solo set until now.

"We're a lot more mature, more grown-up, wiser," Hammett admits of the band now. The guitarist, who sounded satisfied with his solo work but admitted to some nerves in promoting it, nonetheless displayed his confidence in Metallica's legacy with a laugh.

"You know, at this point, we're freaking one of the biggest bands in the world," Hammett says. "You need something the fucking size of a Mack truck to fucking try and screw up our career!"

He continues, "Back then, with Jason, the excuse was that we didn't want it to dilute the effect of Metallica or whatever. Bro, at this point, nothing can dilute what we have. Nothing can. It would have to be so big, you know? I mean, nothing but our mortality. And so we all now realize that, and see each other as just four guys who are artists, musicians that want to express themselves. And why shouldn't we, you know?"

Metallica's development aside, it seems happenstance also pushed Portals to the fore. Hammett had no compulsion to release a solo effort until the pandemic left him with extra time to work on such material, even if he didn't know what he was making yet.

"The timing is right," Hammett says. "And the weird thing is I didn't plan this. I ended up with one track, two tracks until it felt like, 'Wow, I think the universe is trying to tell me something.' It actually felt like that. And it was weird because it was during COVID, and then suddenly I had four tracks, and I was thinking, 'Well, I guess I have to make a choice.' And the choice is that I want to share this with people because I think it's good enough to share, and it would be a bit of a crime not to."

Kirk Hammett performs onstage with bandmate James Hetfield (L) during Metallica's 40th anniversary concert in San Francisco in 2021.
Tim Mosenfelder, Getty Images

The genesis of Portals is in its opener, "Maiden and the Monster," a version of which accompanied a 2017 showing of Hammett's horror and sci-fi art collection. The cinema-inspired number gradually engendered the EP's remaining three songs, which Hammett partially co-wrote with Edwin Outwater, the conductor behind Metallica's S&M2. Outwater plays keyboards and conducts on Portals; other contributors include Metallica producer Greg Fidelman on bass guitar, Jon Theodore and Abraham Laboriel on drums.

But the first Portal listeners heard in earnest was "High Plains Drifter." Released last week (April 15), the Western-evoking rock soundscape now has a music video. (See it below.) However, film fans take note — Hammett said the song wasn't composed with the 1973 Clint Eastwood movie High Plains Drifter in mind.

"The piece originally came out of a flamenco thing that I'd written," Hammett explains. "I played it for a couple of guys in the band, and they didn't show much interest, so I thought I would turn into something else. Then I played it for Edwin, and he loved it, so that's how it became 'High Plains Drifter.'"

Who in Metallica did he show it to first? "I had played it on a classical guitar for Rob [current Metallica bassist Robert Trujillo]," Hammett reveals. "He's like, 'Oh, cool.' And then I played it for our producer, Greg, who's kinda the filter for this stuff, and he's like, 'Oh, OK — I kinda know what you're trying to do.' And that was it! If I play a riff and people aren't going 'Wow!' or standing up or asking to hear it again, it won't work in Metallica."

Blackened Recordings
Blackened Recordings

Not that Portals contains throwaways. Quite the contrary, it serves up whole new worlds of Hammett's creativity for Metallica fans to discover. Including the anthemic "The Jinn" and the ominous "The Incantation," the EP plays like a film — complete with intermission when you flip the vinyl sides. And that's by design.

"This music was created with what I describe as an Audio-Cinematic approach," Hammett says. "They're soundtracks to the movies in your mind."

It's a refreshing tack coming from one of metal's leading guitarists — the same musician who wrote one of rock's most memorable riffs. But now comes the work of getting his new music out there, something the otherwise confident Hammett confided to Loudwire is giving him anxiety in a very relatable way.

"Putting out a solo album, I didn't think about it that much," he muses. "I really didn't. So when it came time to do interviews and, you know, be the face and the voice for this album — it's nerve-racking. Usually, I have the other guys in the band around when we're at this point. But I'm doing it all by myself, so I'm constantly second-guessing myself. 'Why am I doing this? Am I doing the right thing?' I'm a bit insecure about everything about it. I'm just like anyone else, man."

Find Portals on limited Record Store Day exclusive Ocean Blue 12" vinyl at your local record store on April 23. It will also be available to purchase on CD and download from Metallica's official website.

Kirk Hammett, "High Plains Drifter" Video

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