"I felt embarrassed - I haven’t been that angry in a long time." From dinner at Bradley Cooper's to an unplugged mic, the story of Metallica's chaotic Grammys performance with Lady Gaga

It has become one of the most surprising and iconic images to have emerged from the Grammys in recent years: James Hetfield, barrel-chested and iron-lunged Metallica frontman, screaming into a microphone he's currently sharing with generational pop superstar, Lady Gaga. The duo, backed by the rest of Metallica, pillars of pyro and a gaggle of backing dancers as they rip through Moth Into Flame, have had to improvise after an almighty technical hiccup threatened to throw the entire performance into parody. Luckily, it all only serves to make an historic collaboration both more intimate and, somehow, more epic. Disaster averted, basically.

The unlikely team-up took place at the 59th edition of the music industry's most prestigious awards show, which was held on February 12, 2017 at the Staples Center in Los Angeles. On a night also marked by appearances by pop heavyweights such as Adele, Beyoncé, The Weeknd, Daft Punk, Bruno Mars and Katy Perry, Metallica's one-song set promised to inject the evening with some much needed energy and heaviness, not to mention the fact that it'd involve one of the wildest partnerships in Grammys history.

Amazingly, the whole thing came together over just a matter of weeks, following a chance meeting between Metallica's drummer and honorary motormouth, Lars Ulrich, and Gaga herself. "We were asked whether we would come and join the Grammys again," Ulrich explained to Access Hollywood ahead of the performance. "They encourage you to consider, 'Is there some collaboration that you think would be cool?' We said, 'Let's think about it.' And so, I was at a dinner party [with Gaga], and we were sitting next to each other, and we were just basically talking, and I thought, 'Wait a minute, this would be cool.' So I said, 'We're doing the Grammys in a couple of months, do you wanna join us?' and she was just, 'Yeah, that would be great!'"

The dinner party in question was held at the residence of none other than Hollywood A-lister Bradley Cooper, who was in pre-production with Gaga for the film they were both starring in (and that Cooper was directing), A Star Is Born. "I was at Bradley's house with Lars and we were just hanging out," Gaga confirmed to Apple Music's Zane Lowe later that year. The singer was also full of superlatives for Ulrich and his band, adding: "He's amazing! I went to see them live, I've seen them a couple times live, but I saw them recently… and we were watching the show and I'll tell you something, those guys play better than they've played in their whole lives."

And so, a rehearsal studio in LA was booked for the weekend leading up to the big event, and Gaga and Metallica set about reimagining Moth Into Flame in a way that'd both suit its heavy roots while making the most of Gaga's powerful, unique vocals and flamboyant sense of creativity.

"She was in there for two hours before we even got there, working on her moves and thinking stuff up," James Hetfield told Howard Stern in 2020. "She's extremely creative, and she's a fearless artist."

"She was telling me that Metal Militia, which is this deep cut on our first album Kill 'Em All, was her favourite song back in the day," added Ulrich. "She loves metal, has been very vocal about her love for metal all the time and would show up at Iron Maiden shows and Anthrax shows."

Following a successful on-set dress rehearsal before the show began, the stage was officially set and the 59th annual Grammys were underway. And here, sadly, is where things started to go pear-shaped. On the same night that Megadeth were inexplicably played to the stage pick up their Best Metal Performance award to the sound of the house band playing Metallica's Master Of Puppets, it seemed that Metallica themselves were also destined to be undermined once again at the Grammys.

Around halfway through the evening, Orange Is The New Black actress Laverne Cox arrived on stage to introduce Metallica and Lady Gaga's performance...only to forget to mention Metallica at all. Whoops!  “I am so sorry to Metallica and all their fans," Cox later stated on Twitter. "I am told I didn’t say their names during the intro. Love you Metallica. You Rock."

The facepalms did by no means end there. As lashings of pyro burst out across the stage and the band kicked into Moth Into Flame, a metalled-up and go-go-dancing Gaga in tow, it soon became obvious that something was wrong. Namely, James Hetfield's microphone wasn't working. While the band were clearly on top form, as the track's first verse kicked into gear, the frontman's voice was nowhere to be heard as he bellowed into the mic, a quick, confused glance to his side emphasising that he could tell something was up.

Gaga soldiered on, sounding great as she sung her parts, but by the time it came to Moth Into Flames' chorus, it was clear the issue was not getting fixed - almost ninety seconds into the song, and Papa Het was still singing his heart out to absolutely no avail.

"In the heat of the battle, you’re out there, you’re playing," Lars Ulrich told James Corden on The Late Late Show a few weeks later. "When it’s a technical issue, you don’t really know. Is it going to the house? Are the vocals going to the truck? Maybe it’s just the monitor – so you just gotta keep playing."

Thankfully, quick minds prevailed. Gaga, ever the professional, subtly beckoned Hetfield over, and the two sung the track's chorus together on her mic, sharing it for the remainder of the performance. What could have been a total catastrophe ended up being saved at the last minute, and the rest of the song went by without a hitch - and, of course, gave us that iconic shot of the two vocalists side by side. 

Sadly, the technical snafu had already done its damage as far as Hetfield's mood was concerned; as soon as the performance finished, Metallica's usually PMA powerhouse could be seen angrily throwing his guitar off stage. He was still fuming by the time the band got back to their dressing room.

“We get off stage, we get back there and I haven’t seen him like that in 20 years," Ulrich revealed on The Late Late Show. "He was livid. He’s aged really well and is a pretty chilled guy – but the first five or 10 minutes in that dressing room was not a lot of fun.”

"I felt embarrassed," Hetfield told the New York Post. "I haven’t been that angry in a long time. When something out of my control goes wrong, I still get wound up. I’m sure it taps into other stuff from my past, but I felt helpless."

TMZ would report that the unfortunate screw-up was down to a stagehand accidentally unplugging a wire under the stage moments before the performance took place. A brutal mistake, but a mistake nonetheless - and one that Metallica, to their credit, were quickly able to put a positive spin on.

"Like they say, the show must go on," said Lars on The Late Late Show. "We fought through it and a lot of people said that it at least made for great television.” "It ended up being a blessing because I ended up singing in a microphone with Lady Gaga — maybe even more than she wanted," Hetfield told the New York Post. "It felt more like a real collaboration because of that."

In hindsight, Metallica's collab with Gaga is far from the biggest disaster the Four Horsemen have put their name to. A victory snatched from the jaws of defeat, it served as an imperfect if riotously entertaining awards performance unlike any other. Like just about everything else Metallica do, it was certainly unforgettable - and at least we have the flawless rehearsal footage to remind exactly how it all should have gone.

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