Royal Blood on broken ribs, roller coasters and their 'delicate sound'

"Check this out," says Royal Blood's frontman, Mike Kerr, pulling up his t-shirt to reveal a throbbing purple bruise.

"I think," he says, "I've cracked my rib."

Kerr sustained his injury "falling off the drum riser" in Brighton during the band's first show in 18 months, the night before our interview - but he's surprisingly blasé about it.

"I had enough whiskey to fall asleep," he grins, "and a good friend of mine is a paramedic, so I had a shower at my house and went to see him.

"I'm sure it's fine."

It's not the first time the band have been maimed in the line of duty. On their first UK tour four years ago, drummer Ben Thatcher dislocated his finger in the middle of a show.

"He just got some gaffer tape and gaffered his two fingers together and played the rest of the set," Kerr says, matter-of-factly.

Later, on a US tour, their sound technician "lost a testicle", requiring emergency surgery. The details of that trauma are not up for discussion.

Hopefully, then, the band will remain injury-free in the run-up to Glastonbury, where they're third on Friday's main stage bill, just behind Radiohead and The xx.

"Glastonbury is such a big deal," marvels Thatcher. "The Pyramid Stage is the biggest stage in the world."

The set will rely heavily on their second album, How Did We Get So Dark?, released this Friday. It's a record that takes their rampaging rock riffs and pushes them in unexpected directions.

Lead single Lights Out contains bursts of 1970s T-Rex backing vocals, while the piano-led Hole In Your Heart reflects the band's love of R&B.

The BBC sat down with the duo to talk about the perks of fame; the perils of touring; and why they have "a delicate sound". Here are six of their best stories.

Recording How Did We Get So Dark? gave the band the opportunity to experiment with new sounds and techniques. It did not go well.

"One thing we learned is we have quite a delicate sound and once you add things - the wrong things - our whole sound sort of shrivels," says Mike. "Or it capsizes and it doesn't sound like us any more. We've realised a lot of the identity of our music is when me and Ben play together."

"Even the backing vocals - we did try having girls come in and sing, but it just didn't work. It had to be my voice. It had to be just about me and Ben."

Royal Blood are a compact unit. Ben plays drums. Mike plays bass and sings. For some reason, though, this set-up has mystified journalists everywhere.

"'Why are you just a two-piece band?'" Mike sighs. "We get asked that all the time. I guarantee Kings Of Leon have never been asked why they're a quartet."

"Our whole two-piece thing really was not thought about at all," he explains. "Once I plugged in [the bass] and showed Ben the sound, it was like, 'Cool, let's write the songs'.

"I wasn't thinking, 'what if it wasn't just the two of us?'"

"Making a record and writing for that long, you kind of forget what you're doing. And the whole premise of our band is that we're a live band. That's Royal Blood in its purest form."

As they toured the world, Royal Blood picked up a few celebrity hangers-on. After a show in San Franciso, Metallica's Lars Ulrich knocked on their dressing room door, bundled them into the back of a car and gave them a tour of his hometown.

When Ben turned 27, Led Zeppelin star Jimmy Page turned up to his birthday party and ate an apple crumble.

Best of all, the drummer was invited to play Tommy Lee's giant "drum rollercoaster," which travelled, upside down above the audience's heads on Motley Crue's 2015 farewell tour.

"It's insane. He's insane," laughs Ben. "I went down to Wembley Arena, they strapped me in and then, when it started going up, I just thought, 'What am I doing?'

"I hadn't thought about it properly. I was like, 'This is going to be so much fun' and then it was terrifying."

Still, he managed to compose himself and thrash out a few solos.

"It's a different kind of playing. When you're upside down you're fighting the gravity. But it's a roller-coaster. The adrenalin lets you do things that you can't normally do."

Back in 2015, Mike told Q Magazine he'd written "about 50" new songs for Royal Blood's second album. A claim which turns out to have been a big fat whopper.

"I said that two days after we came off tour," he laughs. "They went, 'How many songs have you written?' and I said 50.

"I thought it was funny because we'd only been working on the album for two days."

In the end, though, the band wrote more than that, recording a procession of demos and rough drafts in a rehearsal space in Burbank, Los Angeles.

"A lot of our songs start as very small ideas - something as little as a drumbeat or a riff," says Mike. "Anything creative gets recorded, basically.

"We build a library of ideas, and the ones that really get into our heads and stick around, we usually see them through and build them into songs."

Cracked ribs and broken fingers aside, the band have upped the stakes at their live shows by trying to replicate the layered textures of their second album.

"I was worried we'd snookered ourselves," admits Mike, "I considered getting other musicians in, and then Ben saved the day. It's so impressive when you watch it."

On stage, the drummer not only has to play his own, intricate rhythm tracks, but triggers all the sampled backing vocals and sound effects that pepper the new record.

He does this without playing to a click-track, locked to the tempo of the recorded elements, to stop him drifting out of time.

"There's one sample that's 16 bars long," says Mike, looking worried by the mere thought of it. "It's a long, slow pitch bend that if you play the song too fast, you miss it.

"But Ben's a wizard, so that helps."

"We've stopped playing some of the songs from the first album," says Mike. "There's a few that we've grown out of. There might be the odd lyric that I wouldn't say any more. I guess I don't agree with myself like I used to!"

In fact, confesses Ben, they dropped Careless during their 2015 tour, despite only having 10 songs to choose for the set list from their debut album.

"It is a good song," he says. "We just don't get the buzz from playing it live."

Similarly, Ten Tonne Skeleton, frequently a highlight of their live shows "isn't much fun to play, for some reason".

"It's quite laborious," says Mike, "but as soon as we start into it, you see the crowd go nuts, and that's a real buzz."

How Did We Get So Dark? is released on Friday, 16 June.

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