(Cover) - EN Showbiz - Sam Worthington thinks film accents are like "costumes".

The English-born Australian actor is starring in The Debt alongside Jessica Chastain, Helen Mirren, Tom Wilkinson and Ciarn Hinds.

He plays a young version of former Mossad agent David, who is haunted by repercussions from a top-secret mission he carried out with another two agents in the 1960s.

The role required Sam to master a German accent, and the star admits to struggling with the challenging task.

"I find them always hard, it's like a costume," he told MTV. "But to learn German on top of an Israeli lilt thrown on top of an Australian accent with a guy who's not very good at accents anyway, it was doubly hard. You just put in the effort, and Jessica Chastain is great at accents she kind of helped me through it.

"I drop accents. The character traits I keep and the emotions I keep, but the accents and the costume I don't take home."

Jessica appears as a younger version of Helen Mirren's character in the thriller. The 30-year-old American actress says the role required a lot of arduous studying which made her feel like she was back in education.

"I always do preparation but it was very strange. The preparation for this was more exhausting than filming the movie. About three and a half months before filming started, I started learning Krav Maga. I took a beginner's course Berlitz in German, I started learning the accent. I started watching a lot of Helen Mirren. I read about the Holocaust and the medical experiments, which was devastating to read about the atrocities that happened then," she recalled.

"It really was like going back to school for me." (C) Cover Media