Country songstress Taylor Swift did a "fantastic job" of playing a bad girl in her latest music promo.

The pretty singer portrays a girl who gets sucked into a troublesome relationship with a bad boy in the new video for her latest single 'I Knew You Were Trouble'.

He love interest is played by Reeve Carney, and the actor says Swift - complete with newly-dyed hair - took to the on-screen role perfectly.

He told MTV News: ''She's not a full bad girl. She's someone who's drawn in by the temptation and the thrill of it all, but at the same time, she's halfway: She's got one foot in and one foot out. 'I think she did a fantastic job, and I think she looked good with the pink hair. I like her normal hair, but I thought it was cool a cool thing to experiment with.''

Carney thinks Swift could have a promising career on the big screen after filming alongside her.

He added: ''It was a great acting piece for her, too. I thought she was fantastic. I kept telling her, 'Man, you're such a natural. You've got to do more of this.' And I don't know if she was listening to me or not, but I think she definitely has a natural ability for sure.'' Watch the new video here: