Sam Claflin has admitted that he was 'out of depth' when he was cast as Billy Dunne in Daisy Jones & The Six.

The actor, 36, confessed he hadn't heard of the Taylor Jenkins Reid book the series is based on and described becoming an onscreen rockstar as 'a very huge learning curve'.

Speaking to

'I only ever hear about the projects after I know there's a script out there, and someone says, "Oh, did you realize it's a novel?"'

'I genuinely had to go online and google whether Daisy Jones & The Six was an actual band.'

'My knowledge of 1970s rock and roll is very, very bad, so this has been a very huge learning curve for me.'

He added: 'This is the most petrified I've ever been about a role, and I think it's partly because I knew how far I had to come. I was so out of depth.'

Detailing his busy schedule: 'I'd wake up in the morning, go straight to the studio and learn guitar for an hour, then I'd go for a costume fitting.

‘I'd have an accent lesson with a speech and dialect coach, then I would probably record a bit or go and practice.'

He continued with singing lessons, followed by a meeting with a movement coach and a personal training session leaving Sam 'absolutely knackered' and worrying he could pull the role off.

Discussing re-listening to his first voice lesson years later, he said: 'I'm shocked that they saw something in me, honestly.

'I think the one thing I will say is that I'll forever be grateful for the belief the producers and the music team had within me.

'You know when you listen back to an interview you've done or a voicemail you've left, and you hear your voice, and that kind of like, "Ugh," that cringe moment?

'I get that in spades when I'm singing … I just don't think I have the ego to be a musician. I don't have the self-belief.

Daisy Jones & The Six's lead role is played by Riley Keough, the granddaughter of Elvis Presley, who Sam praised for helping him during filming.

He insisted: 'The one thing I'll say about Riley is she does not carry the weight of her granddad on her shoulders.