Rita Ora found learning lines for her Hollywood movie debut "incredibly difficult".

The platinum blonde star is already a star in the music world, but is looking forward to getting her claws into acting too.

She plays Mia Grey in the forthcoming Fifty Shades of Grey flick, which has been adapted from the best selling steamy novel of the same name.

While the 23-year-old is a seasoned performer, talking with an American actress threw her slightly.

"It was incredibly difficult," Rita confessed to British newspaper Daily Star.

“I had to have someone in my ear telling me what to say before I said it.

“I was so nervous I forgot everything that I had learned."

The film co-stars Northern Irish hunk Jamie Dornan and Dakota Johnson in the lead roles, and is slated for a 2015 release.

Far from worrying too much about her day job, Rita is already pondering what she'll wear to the opening of the film.

"I’m thinking about what to wear at the premiere. I might bring a fan or do something. It would be like a nice little experience for someone to come with me, you know?” she smiled.

She's also taken quite a shine to co-star Jamie, who plays the seductive Christian Grey. The former model shaved off his trademark face fuzz for the role, and Rita thinks the new look suits him just fine.

"I am always a beard fan, I like it to be scruffy scruffy.

“But a nice little baby shave is not bad either, like a baby’s bum – it is always a nice touch," she mused.