Lupita Nyong'o was unfamiliar with the story of The Odyssey.

The 43-year-old actress portrays the dual role of Helen of Troy and Clytemnestra in Christopher Nolan's upcoming epic but explained that she had to familiarise herself with Homer's ancient Greek literature, which serves as the source material for the movie.

Speaking to ELLE magazine, Lupita said: "I really had no idea what The Odyssey was. I was like, 'Oh, snap, I don't know the first thing about this.' So it was a crash course. I picked up the books and read them immediately. I have this film to thank for my Greek mythological education."

Nyong'o also relished the chance of getting to work with acclaimed director Nolan and was impressed at how much the Oppenheimer filmmaker involved the cast in aspects of the production process.

The 12 Years a Slave star said: "He has quite an enigmatic persona, but working with him was so accessible. He's really great with actors. I felt supported. I felt challenged. And what I love most about his approach is that he really wants to know what the actors think. He really gives us the responsibility and the authority to advocate for our characters. You're very much a part of consultations about hair, makeup, wardrobe, all of that."

Lupita has faced racist critiques after being cast as Helen of Troy - known as "the face that launched a thousand ships" - but is paying little attention to what her detractors say.

The Oscar-winning actress said: "I'm very supportive of Chris' intention with it and with the version of this story that he is telling. Our cast is representative of the world. I'm not spending my time thinking of a defence. The criticism will exist whether I engage with it or not.

"It's quite something to be a part of The Odyssey, because it is so grand. It spans worlds. So that's why the cast is what it is. We're occupying the epic narrative of our time."

Nyong'o explained that it is impossible to "perform beauty" and that she based her depiction of Helen of Troy in The Odyssey - which will be released in July and also stars Matt Damon, Tom Holland and Anne Hathaway - on Nolan's script.

She said: "You can't perform beauty. I want to know who a character is. What is beyond beauty? What is beyond looks? That's the thing about doing such a well-known text, which has been studied and interpreted and derived from. The research could be endless. The good thing about working with a writer like Chris is that it's on the page. The investigation starts with the pages you're given. That's what I based it on."

The July/August issue of ELLE UK is on sale from 18 June.

The full interview with Lupita Nyong'o can be read at https://www.elle.com/uk/the-odyssey/