Every so often you have to pinch yourself in this industry, and standing there, watching Ethan Hawke sing Waterloo Sunset live on a film set, was one such moment. The only downside was, as one of our favourite songs of all time, we had to listen to it about fifty times over. Which isn’t fun whoever is on lead vocals.

This indelible moment came on the set of Juliet, Naked – the latest cinematic adaptation from the work of Nick Hornby, directed by Jesse Peretz – the founding member of successful band The Lemonheads. We were fortunate enough to spend a day on the London set, where we spoke to Ethan Hawke, who plays has been singer-songwriter Tucker Crowe, and Rose Byrne, the lead role of Annie.

For Hawke, it was a character – and a world – he felt very close to, which he felt had a positive impact on his performance.

“I played Chet Baker a couple of years ago and that was kind of easy in a way because I relate to and I know those people. Actors and musicians are not that different, so it’s a world I’m familiar with. It’s easier for me than playing a drone pilot where I have to learn about the whole world. I enjoy it too, I enjoy making movies about something I know about,” he said.

“Sometimes it’s fun to play a character that I feel like I know, it’s in my wheel house, so to speak. I’m friends with Charlie Sexton and when I told him about this he said ‘Oh you’re playing me’. Which isn’t a terrible example, though Charlie of course never left music. There’s nobody I based it on, though.”

Sat in a dusty and discarded room on the top floor of a multi-storey building in central London, Hawke was also quick to tell us of his experience collaborating closely with Byrne, for the very first time in their careers.

“Rose reminds me of myself a little bit,” he said. “She’s been doing it since she was young and she’s very relaxed about it and certain things come easy for her and people take it for granted. I find her an absolute pleasure.”

“I really enjoy acting with women. A couple of the best experiences of my career have been with Sally Hawkins, and Sarah Snook. Also Winona, Angelina and Julie Delpy, I’ve had a long history of getting to work with really talented women.”

When we spoke to Byrne, in another dusty and discarded room – this time in the basement – she told us why signing up to this project was a complete no-brainer.

“I read the book when it came out and loved it, so when I found out it was being done I was immediately intrigued, so it was kind of a no-brainer. I was a fan, literally a fan. I met Nick Hornby the other day on the set and I was extremely nervous because I think he’s such a brilliant writer,” she said.

Though the start of Hornby’s career was generally centred on male protagonists in his novels, as he gets older we have seen something a shift towards female characters, prevalent in his screenwriting work too, as he penned the scripts for films such as Brooklyn and Wild.

“Brooklyn and Wild were fantastic,: Byrne said. “Annie is a really complicated character and it’s great to have that, and to have the book there as a reference. Obviously you have to let go of it at some point because it’s a different thing entirely, but Nick does create complex women, for sure.”

Pregnant at the time the interview took place (which was well disguised on camera – the magic of cinema, eh?), it was the end of a long and tiring day. But the Australian actresses’ enthusiasm had not yet wained. Particularly when we discussed her fondness for fellow Aussie Kylie Minogue – after getting on to the theme of obsession, which plays a big part in this production.

“When I was a teenager I had intense obsessions, like Kylie Minogue, I was a huge pop fan, I was very uncool. I wasn’t a hipster. She’s fabulous, she’s an icon, but back then it was before her transformation I guess and I loved her for so long, but in any case, this does tap into that obsessive quality that I can relate to, but more from being a teenager, there’s something juvenile about it.”

Talking of being a fan, she also explained how much fun she had with Ethan Hawke on set, who she has long admired.

“I’ve been enjoying it so much, he has this innate quality and you forget he’s an incredibly accomplished screenwriter so his ideas for the script and story are essential and have helped so much in the development of this film. He’s passionate too, and he’s been doing this a long time but he’s always passionate. And charming, yeah, he has this charm. Such a varied career too, I’ve loved it,” she finished.

It’s hard not to be a fan of Hawke, as an actor who is impossible to second guess, such is the eclectic range of roles he has undertaken across his illustrious career. We asked him about his choices, and whether he actively seeks out roles that are different to what he has previously done before.

“Luck is the residue of design, right? I actively seek them out,” he said. “I think it’s because I started so young and because I have a limited belief in my own ability to excel as an actor that I enjoy putting myself in different environments. It’s a way of me shaping my own performances, is to put myself in different kinds of movies. Like, there’s a different geometry to making a horror film than there is a romantic comedy. There’s a different geometry to making an art film. If you’re making Boyhood or the Before trilogy, what the audiences are expecting and wanting is different to what they want from Training Day. There’s a path to a cop genre and you have to work within that path and deviate and if you don’t deviate at all then it’s boring and if you deviate too much you don’t play to the rules of the genre. It’s very strange. But I enjoy doing different kinds of movies because it makes me really curious. A lot of actors who have acted for as long as I have, you know, they get burnt out pretty easy. So I like to shake it up.”

Though following your nose and chasing roles that are creatively stimulating does have its downsides, for he admits that the path he has taken has not always reaped financial reward – especially in an industry that he feels doesn’t do enough to support dramatic endeavours.

“If you’re a dramatic actor it’s a strange period right now,” he continued. “Because studios aren’t really interested in making dramas, they make one or two a year if Ridley Scott or Spielberg are directing them, but you are forced to make them outside of the mainstream industry, which means you don’t get paid to do them. For me the hardest thing about being a professional actor with four kids, is doing the kind of work I want to do and making a living, because it’s got cheaper and easier to make a film, it’s just really hard to get it released. Moonlight is the great exception, right? A couple thousand Moonlights get made a year, meaning, people making a movie on the cheap, everyone doing it because they love it, but do that for 30 years and every now and then one turns out to be Boyhood, sometimes they don’t even come out. It’s a strange time.”

Finally, before we left we couldn’t help but ask him about Waterloo Sunset and whether he had as much fun singing it all day, as we had hearing it. Turns out, it took a little bit of persuasion to ensure the song made the film.

“My son is falling in love with the guitar. We always loved that song, I put in on a playlist when they were kids and it’s one of the first songs he wanted to learn on the guitar, so when Jesse and I were trying to figure out what song this should be, I said, ‘what about Waterloo Sunset?’ and he said it’s always been in his top ten of all time, but it was the wrong year. Some of the producers didn’t want it, then the cinematographer said it’s always been his favourite song, so it was an accumulative effect of everyone wanting it. It was important to find a song that was extremely well known but also had some uniqueness to it,” he finished.

Juliet, Naked is out in cinemas now