Australian star Abbie Cornish learnt Spanish and gave up five months of her personal life for The Girl, a movie about the relationship between a Texas woman and a little Mexican girl who lost her family trying to cross the border illegally.

Cornish, who has appeared in such films as Bright Star, Sucker Punch and Limitless, plays Ashley, a single mum who had custody of her son taken away by social services.

Almost three-fourths of the acting is in Spanish, a language the 30-year-old Australian never spoke before at all.

Looking for easy money, Ashley decides to act as a "coyote", or people smuggler, helping a Mexican family cross the border into the US illegally, but the venture ends in tragedy and with the responsibility of caring for a little girl left all alone in the world. Their unusual friendship will change her life.

"It was an experience that absorbed me completely," the actress told EFE in an interview before the movie's US premiere this Friday.

"I gave up my personal life for five months. There was nothing else I could do. But it was easy because I'm single, I have no kids, I live alone, and the truth is I'm a workaholic. I don't have any other responsibilities."

For Cornish, the shoot in Mexico was an experience that left its mark on her and which she'll never forget. In fact, she decided to film all the details of the production with her own videocamera and, after editing more than 15 hours of material, posted parts of it on Facebook and Twitter.