Keira Knightley is ''terrible'' at keeping secrets.

While the 28-year-old beauty plays the love interest of a CIA agent in new film 'Jack Ryan: Shadow Recruit', she insists she could never be a covert operative herself because she would end up spilling all the classified information.

She said: ''I'm terrible at keeping secrets - it would come straight out of my mouth, so I'd be an awful CIA agent.''

Keira will next be seen in a singing role in 'Can a Song Save Your Life?', which co-stars Maroon 5 hunk Adam Levine - who was recently voted Sexiest Man Alive - but the British starlet says the singer didn't help her find her voice on set and left her to her own devices.

Asked if Adam gave her tips, she said: ''No, he didn't, actually! He's one of those annoying singers that just kind of thinks everyone can sing, kind of like, 'I don't know ... just do it!' ''

Like his co-star, 'Jack Ryan' leading man Chris Pine will also serenade audiences in Disney's new fairytale-themed musical movie 'Into the Woods', but the 33-year-old stud isn't convinced his vocals are entirely up to scratch.

Chris says he took singing lessons ''for months'' to prepare for the role of Prince Charming, but his co-stars weren't overly complimentary of his efforts.

Speaking at the European premiere of 'Jack Ryan' in London's Leicester Square on Monday (20.01.14), he told BANG Showbiz: ''I got kind of, like, vague, casual smiles - nothing too effusive!''