Meryl Streep was joined by co-star Philip Seymour Hoffman at the premiere of their new film, Doubt.

Directed by John Patrick Shanley, the film sees the actress play a nun who suspects a priest is molesting a boy at the Catholic school where they work. She spends much of the movie plotting to find evidence against the priest, played by Hoffman.

Streep said of her character: "Her faith is tried in this film. And human beings are very complicated. Why she is the way she is, why Father Flynn is the way he is, why Viola Davis' character Mrs Muller is the way she is - it's by virtue of our circumstances.

"(It's about) what we went through, what our personal pain was. I think they really got that in the film. So I'm proud of it."

The 59-year-old last starred in Mamma Mia, which has become the highest grossing Brit film of all time.

Doubt is released in the UK on February 6.

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