Radiohead guitarist Jonny Greenwood has announced that he’s releasing a soundtrack album of his music for new Princess Diana biopic, Spencer.

Spencer will be the latest from director Pablo Larraín, starring Kristen Stewart in the lead role as the late Princess Diana. The film also marks Greenwood’s ninth soundtrack, following four films with Paul Thomas Anderson including There Will Be Blood and Inherent Vice, plus You Were Never Really Here for director Lynne Ramsey and his first film score Bodysong in 2003.

The release date for the soundtrack, which will be released on Mercury KX,  is expected to be announced once a UK release date for the film is confirmed. The movie premieres tonight (September 3) at The Venice International Film Festival, and has a US cinema release on November 5.

In an exclusive interview with NME, Greenwood admitted he initially struggled not to make the film’s music “sound like the theme to Antiques Roadshow”. We also asked him about what’s new for Radiohead, and what’s to come from new side-project The Smile (also featuring Thom Yorke along with producer Nigel Godrich and drummer Tom Skinner of Sons Of Kemet).

Hello, Jonny. How did you become involved in the Spencer soundtrack?

Jonny: “I had an email from the director, Pablo Larrain. I didn’t know his work, so he sent me his film The Club, which I found very affecting. I enjoyed corresponding with Pablo, firing each other up with enthusiasm about what the music could be. He’s a very energetic, positive person.”

How did you want to make your music different from other royal biopics?

“I explained to Pablo that there’s lots of baggage attached to classical music in films about the royals. You either use actual Handel or pastiche Handel. I watched a few royal films, which were full of sweeping shots of Buckingham Palace, with fanfare horns and tinkling harpsichords on top. I wanted instead to emphasise how chaotic and colourful Princess Diana was, in amongst all that baroque tradition. It’s what the film does too.”

How did you achieve that?

“I suggested we get a baroque orchestra in, so I wrote music in that regular royal style, with kettle drums, trumpets, harpsichords and pipe organs. Then, while they were playing, we substituted the orchestra with free jazz players. They could play those instruments, but we had it mutate into a free jazz performance. That was so exciting, the jazz players were just amazing. The trumpet player, Byron Wallen, blew my mind. That said, at first they were too restricted by the chords. It was like they were trying to improvise to the theme from Antiques Roadshow. The key was to still sound vaguely baroque, while leaving enough space for true anarchy and chaos.”

How does the film make you feel about Princess Diana?

“It makes you appreciate how claustrophobic her life must have been. It’s set over three days in Christmas 1991. Family Christmases are a nightmare anyway! To have that, and then be presented with eight dresses, the order you have to wear them in, be told where you have to be and what you have to say? It doesn’t look fun.”

How do you view the Royal Family in general?

“I go along with Stephen Fry’s view, which is that the Royal Family are an absurd institution, but getting rid of them wouldn’t change anything. Like he says, if you look at the other European countries which have kept their Royal Family, it’s amusingly the most liberal and socially advanced countries, like Sweden and the Netherlands. I don’t see that France is any freer or more liberal than we are, so keeping the Royals is preferable to having whoever would be President. Who should live in those palaces? It might as well be someone who’s a bit peculiar.”

After nine soundtracks, do you feel at home as a film composer?

“I’m still doing it wrong, really. I still present directors with hours of music which need to be fitted into scenes lasting a few minutes long at most. I haven’t done a car chase, and I rarely have to make music that ducks out of the way for dialogue. That’s real composing. I’m still wedded to the idea that it’s good to record music without click tracks, or worrying too directly that it’s wedded to the scene.

“It’s why l like starting early on a film, presenting directors with music while they’re filming. That way, directors can play my music on set, which can inform the atmosphere of some scenes. It makes a lot more sense to me than being told: ‘Here’s the finished film, you’ve got three weeks to put the music on top’. I think: ‘You thought about the make-up six months ago, why didn’t you think about the music then too?’ That seems a strange way to do it.”

Does getting it wrong ever mean presenting ideas that would just never work in a film?

“Sure. I’ve just done another film, Power Of The Dog, with Jane Campion. I was seriously trying to make out that the banjo could be used as a contemporary classical instrument over atonal strings. You’ll be unsurprised to learn it doesn’t work. The banjo can be dark and sinister, so that worked. But, as soon as you try to treat it like something you can play along with, it just sounds comic. That was pretty terrible. To get out of that dead end, I started playing the cello like a banjo, which seems to suit the film.

“There wasn’t any of that on Spencer. But I originally started it by looking at the music Princess Diana was into, thinking maybe that was the way into her skull. The trouble is, that leads to lots of Dire Straits, Go West and Andrew Lloyd-Webber. There are probably out-takes of me arse-ing around with bad ’80s keyboards! I felt like that stuff didn’t need pastiching. Plus, the film is set in 1991, so it was as sensible as any other approach to go with ’70s free jazz.”

You’ve been busy. You also recently started a new band in lockdown…

“I have. The Smile came about from just wanting to work on music with Thom in lockdown. We didn’t have much time, but we just wanted to finish some songs together. It’s been very stop-start, but it’s felt a happy way to make music.”

When will we hear The Smile’s album?

“Lots of it is just about finished. We’re sitting in front of a pile of music, working out what will make the record. We’re thinking of how much to include, whether it’s really finished or if there are a few guitars that need fixing. I’d hope it’ll come out soon, but I’m the wrong person to ask.

“I’m the most impatient of everybody in Radiohead. I’ve always said I’d much rather the records were 90 per cent as good, but come out twice as often, or whatever the maths works out on that. I’ve always felt that, the closer to the finish, the smaller the changes are that anyone would notice. I’d have said The Smile could have come out a few months ago, but it wouldn’t be quite as good. I’m always impatient to get on and do more.”

You played ‘Skating On The Surface’ at the Glastonbury livestream. It started out when Thom played it with Atoms For Peace, then Radiohead played it in 2012. How has it become a Smile song?

“Well, I don’t know if it’s definitely a song for The Smile. We’ve recorded everything we played at Glastonbury, but I don’t know if it’ll be on the album. Like I say, we’ve got to go through everything in the pile. I’m very relieved that everything for Spencer finishes this week, because next week we can get into The Smile and make sure that’s in a healthy state.”

Will you tour The Smile?

“No idea. It’s undiscussed and undecided. But it feels like we now have to start engaging with the outside world, having worked on this stuff alone. That’s the test, when people finally hear it. I’m looking forward to that, as what the outside world makes of you is more than half the reason for doing it. I’ve never understood the idea of music for its own sake. I remember bands I like who brought out albums I thought were disappointing. The fear of that is a big one. I’ve not met anyone who claims they don’t think about that stuff.”

The safe option for acclaim is always reissues. What about these rumoured 20th anniversary reissues of Radiohead’s ‘Kid A’ and ‘Amnesiac‘?

“We talk about it, but I don’t know. That stuff takes a lot of time and, going back to the desire to bring out new music, that’s usually more interesting. It’s nice to go back and look at the old stuff sometimes, though, so we’ll see.”

Has your claustrophobia changed the type of music you’ve been writing in lockdown?

“It’s led me to being less scared of long music. I always have a panic that, after three minutes, I’m bored and everyone else must be too. I’ve just written a piece of music for church organs that’s eight hours long. I don’t know if it’ll ever be played. That’s so pretentious now I’ve said it . But I’m really interested in why everything bores me after three minutes, and I’m trying to break that. I was raised with the idea of the joyous three-minute song. It’s why I love bands like Pixies and Magazine, all those bands who managed to be motivated by making sure their message wasn’t boring. At the same time, there’s the deep listening movement, forcing yourself to slow down to whatever the pace of the music is.”

Which do you prefer?

“I can’t decide which is the best approach. With The Smile and Radiohead, I’m constantly thinking: ‘We could take out half a verse here’ and panicky wondering: ‘How can we move this from four minutes to three minutes?’ And that’s good, to be constantly worried about fat and things that don’t need to be said. But you also have Indian music which holds your attention for 20 or 30 minutes, because there’s huge tension involved in melodies that only move occasionally. And, when they do move, it’s a real release of tension. That music is nothing to do with relaxation or being treated as an adjunct to massages. It’s enormously anxiety-inducing music, which wonders how the player is going to devise something with so few notes, how he’s going to break out into a new note. When you listen to it like that, it’s a far more involving experience.”

While we have you, what’s happening with your record label, Octatonic?

“The two recordings we made were great, but they seemed to not really connect with anybody. It’s the balance between being enthusiastic and wanting to promote that music, and the fear it’s starting to feel like a weird vanity project. That would just be awful. I’m waiting to see if people are interested enough in another recording. If they are, great. If not, it’s out of my hands.”

Is there a film director you’d love to work with on a soundtrack?

“I don’t really think about it in that way. I’m getting annoying emails from Paul Thomas Anderson about a couple of potential projects! They sound really interesting and peculiar, so I’m thinking about those while I wander around. I really enjoy the thinking time of music, drifting off and wondering how to describe in music what PT is talking about. It’s very self-indulgent, but really fun. I’m an extremely lucky man.”

Spencer premieres at Venice Film Festival on September 3 and is due to be released in cinemas in the US on November 5.