It seems like this album was created over a long period of time, but it still sounds very cohesive. Did it all start to fall into place during the latter stages of recording?

James Hetfield: “It usually does. The road narrows, you know? You start with 800 riffs and you whittle it down to 50 with the help of others in the band. Then you pick ones you want to jam on.

There was a riff, it’s called The Parking Lot, and we thought that was an A+ riff and was going to end up as a song, but it never did

“I think it all kind of started with the [2014 song] Lords Of Summer when we were doing tons of Summer festivals. That was kind of the springboard because once you open that pandora’s box of riffs, you don’t want to stop. You start picking out stuff… actually in the movie [Metallica’s thriller/concert film hybrid, Through The Never] there were a couple of things that didn’t show up. There was a riff, it’s called The Parking Lot, and we thought that was an A+ riff and was going to end up as a song, but it never did. But it’s all springboarding.

“You narrow it down and start making some songs. I think when you say cohesive, that’s good, but to me they all started sounding the same after a while. We needed some variety, we need some slow stuff, some really fast stuff, so it took a little while.

“Mainly because of the time between albums, six to eight years and you’ve got a lot of material. And there’s also the part of me that wants to say, ‘Well fuck all that, let’s go and write some riffs now!’”

It seems like the song Hardwired came together pretty fast?

James: “Yes, that was the one where at the end [of the process] we stood back - which is tough to do sometimes after sporadically writing a record over two years - and said, ‘Oh wait a minute. We need to open this with something really in your face-style, so it was really easy and quick. And it was like, ‘We’ve got to do more of this stuff.’”

Here Comes Revenge is reminiscent of The Black Album-era sound. Was that a subconscious thing?

James: “I don’t think it was either overt or covert really. We sat there and were thinking, alright, Death Magnetic… what do we do after that? My take usually is shorter, more muscly songs and Lars claims a more organic approach [chuckles] where there’s no limit and you just keep writing. So between the two we get a little of both.

I wanted Kill 'Em All simplicity and a little more of the kind of misty layering and colourations of The Black Album

“I wanted Kill 'Em All simplicity and I also wanted a little more production than Death Magnetic with the kind of misty layering and colourations of The Black Album. So there’s a little bit in there at times, and then there’s some really, really simple stuff.”

Kirk Hammett: “I love that groove, I love the swing and the bounciness. For me the best rhythms to solo against are the rhythms that have a swing to them. As a guitar player I’m all about it - bring on the groove, bring on the swing. It just makes my job so much easier rather than soloing over a 5/8 time change and three chord changes within one bar. There’s a certain beauty to that, a type of art that’s being represented by that thinking.”

Dream No More even has a little pause before your solo that’s reminiscent of Sad But True…

Kirk: “Yes, it’s interesting that you say that because both those songs are in D tuning; maybe it’s something about being in D tuning that makes me play that way. But all this stuff, it just came out. It wasn’t really planned or anything, and I love that aspect of it.

The song Am I Savage sees a lot more of your blues influence come through tonally, too…

Kirk: “I’ve got this one guitar… its name is Greeny [Peter Green's 1959 Les Paul, which Kirk discusses at length in a previous interview]. I only have a couple of guitars that have actual names and one of them is The Mummy [KH-2] and one of them is Greeny. And when I have that guitar in my hands, there are certain licks that just want to come out. And for that solo, I don’t know if I played Greeny or not, but most likely had Greeny in my hands for warming up or was using it to play a solo and switched guitars, I’m not sure.

“But Greeny has a way of wanting me to play Peter Green and Gary Moore licks. It’s just one of those things. And the blues, the blues thing has always been with me since the very beginning, but I got really, really heavily into it in the 90s. But it’s really an example of how much of an effect that guitar has on me.”