A Dangerous Method is a 2011 historical film directed by David Cronenberg and starring Keira Knightley, Viggo Mortensen, Michael Fassbender, and Vincent Cassel. The screenplay was adapted by writer Christopher Hampton from his 2002 stage play The Talking Cure, which was based on the 1993 non-fiction book by John Kerr, A Most Dangerous Method: The story of Jung, Freud, and Sabina Spielrein.

The film marks the third consecutive and overall collaboration between Cronenberg and Viggo Mortensen (after A History of Violence and Eastern Promises). This is also the third Cronenberg film made with British film producer Jeremy Thomas, after completing together the William Burroughs adaptation Naked Lunch and the J.G. Ballard adaptation Crash. A Dangerous Method was a German/Canadian co-production. The film premiered at The 68th Venice Film Festival and was also featured at the 2011 Toronto International Film Festival.

Set on the eve of World War I, A Dangerous Method describes the turbulent relationships between Carl Jung, founder of analytical psychology, Sigmund Freud, founder of the discipline of psychoanalysis, and Sabina Spielrein, initially a patient of Jung and later a physician and one of the first female psychoanalysts.

Keira Christina Knightley ( /ˌkɪərə ˈnaɪtli/; born 26 March 1985) is an English actress and model. She began acting as a child and came to international notice in 2002 after co-starring in the film Bend It Like Beckham. From 2003, her appearances in the Pirates of the Caribbean film series took her to much greater prominence. In 2008, Forbes claimed Knightley to be the second highest paid actress in Hollywood, having reportedly earned $32 million in 2007, making her the only non-American on the list of highest paid actresses.

Knightley has appeared in several Hollywood films and earned nominations for the Academy Award for Best Actress and Golden Globe Award for Best Actress for her role as Elizabeth Bennet in Joe Wright's 2005 adaptation of Jane Austen's novel Pride and Prejudice. Two years later she again was nominated for the Golden Globe Award for Best Actress, as well as the BAFTA Award for Best Actress in a Leading Role for her performance in Atonement.

Knightley was born in Teddington, London, England, the daughter of Sharman MacDonald, an award-winning playwright, and Will Knightley, a theatre and television actor. Her father is English and her Scottish mother is of half Welsh ancestry. She has an elder brother, Caleb.^{[citation needed]}