British actress Keira Knightley has revealed she was drawn to play 'Cathy Muller' in the newly released 'Jack Ryan: Shadow Recruit' because she was sick of portraying tragic heroines. The 28 year-old, who stars opposite Chris Pine and Kenneth Branagh in the Tom Clancy inspired movie, spoke about the "fun" role at the film's European premiere in London's Leicester Square.

Keira Knightley
Keira Knightley as 'Kathy Muller' in 'Shadow Recruit'

In recent years, Knightley's roles have something in common, at the end of the film she dies. This occurs in Anna Karenina (2012), A Dangerous Method (2011), Never Let Me Go (2010) and 'Seeking a Friend for the End of the World' (2012).

The Academy-Award nominee revealed, "I think when I finished doing Anna Karenina I realised that I'd been playing characters that pretty much died or something horrendous happened to them for about the last five years and I fancied doing something fun."

Continuing "I've never done a thriller before, and it's been a genre that I've really liked. It's a difficult one because you combine action with proper storytelling and it needs a proper storyteller to do it, so I was excited by the challenge."

Watch the 'Jack Ryan: Shadow Recruit' trailer here

Unlike the other movies based on Tom Clancy's famous character, 'Shadow Recruit' portrays the origins of Jack Ryan and how he began his career as a field agent as well as the start of his relationship with physiotherapist, Cathy Muller (Knightley).

The movie isn't based on any novels by the late author, but is a reboot of the old 'Jack Ryan' film series, depicting a completely original story. Knightley was also attracted to the role to see how a government agent balances work and a relationship.

She stated, "As far as the relationship between Jack and Cathy goes I was interested with the idea of what happens to a relationship when there is a secret, when there is something that can't be discussed, something that can tear two people apart even though they are completely in love."

Concluding, "I thought that was a very interesting part of the story, as far as what people who work in secret services have to give up and the emotional toll that it takes on them."

'Shadow Recruit' hit theatres in the US on January 17th 2014.

Chris Pine
Knightley stars alongside Chris Pine who plays 'Jack Ryan'