Film character 'Duffy as a girl'
Duffy has told how she based her character in new film Patagonia on her own experiences as a "mischievous teenager".
The Mercy singer - who makes her acting debut in the film as an aspiring singer living in a caravan in North Wales who strikes up a romance with a young boy visiting from Patagonia - attended the premiere at London's Odeon cinema in Covent Garden.
Duffy revealed: "I based her on who I used to be - this girl who was a bit of a misfit, didn't fit into the small town, who used to long for the big smoke. So it was nice to go back and be captured that way."
She went on: "I don't know if it felt like acting really.
"I heard a really great bit of advice once - the way to be a good actor is to not act. It just felt like being... I was just existing on screen, rather than having to pretend. There was no pretence really."
Duffy insisted that even filming love scenes with co-star Nahuel Perez Biscayart were not too much of a challenge.
She said: "I just had to try to imagine what it would be like, go back into being this love-sick teenager.
"They weren't too difficult really, I didn't really feel out of my depth, it all felt quite comfortable, quite safe."
She laughed: "No nudity though, so that was OK."
The film is directed by Marc Evans and also stars Brother And Sisters actor Matthew Rhys and Evans' wife Nia Roberts.