(Cover) - EN Showbiz - Anne Hathaway won't give any secrets away about The Dark Knight Rises because she "signed a blood oath".

Directed by Christopher Nolan, the action picture will be the third instalment in the moviemaker's critically acclaimed take on the Batman superhero franchise, and is scheduled for release next year.

Anne stars as Selina Kyle/Catwoman in the film, although is keeping any movie secrets well guarded.

"I signed a blood oath," she laughed to Total Film. "Bloody thumbprint on paper."

Anne is less known for her action roles, having predominantly shone in romantic comedies such as Love and Other Drugs or gritty dramas including Rachel Getting Married. The movie star has been embracing the change though, as she feels experimentation will make her a greater thespian.

"I went after it because it was the best role and Chris was willing to meet me," she enthused.

"I want to be the best actress I can be and that means working with the best people and taking the most challenging roles.

"That's the plan so far and it's led to some really exciting places."

Although Anne won't be drawn into giving away Dark Knight spoilers, she was prepared to express her enthusiasm about the picture, teasing that it is "going to be really good". (C) Cover Media