Keira Knightley movies are fun, hot and usually hits. Knightley was nominated for an Oscar for her roles. The Pirates of the Caribbean star has acted with some of the best actors in films. Keira said yes to the film "Jack Ryan," just for the chance to work with Kenneth Branagh. But Keira has a secret: Keira Knightley suffers from stage fright on movie sets.

Speaking to Glamour magazine, Knightley admitted "I have really suffered from stage fright, or actually camera fright. [Because] you are presenting layers and layers of pretending, and it's not just you but other people in charge of your face or your body or your hair."

Keira Knightley talked to Glamour about her new film "Begin Again," a romantic comedy co-starring Maroon 5's Adam Levine.

Levine was also nervous while shooting the movie. Last month, the Maroon 5 singer told people "I was worried, but I had to pretend like I wasn't/ I kept thinking, 'I'm an actor. For this next two weeks, I am an actor.' I crossed my fingers and hoped it turned out fine."

"He did play a d-head very well," Knightley dished in the July Issue of Glamour. "Actually, I admire him being so willing. To play a d-head is quite a big thing when you are trying to break into film and you want to be likable."

In "Begin Again," Adam Levine and Knightley play a musical couple. Keira plays a songwriter (Knightly plays guitar and sing in the movie) and Levine plays a rock musician who just got signed by a major label. The films also stars Mark Ruffalo, Catherine Keener, Hailee Steinfeld and CeeLo Green.

Keira Knightley is also starring in "Jack Ryan: Shadow Recruit." She took the part to lighten herself up after moving into dark roles. "I got to the end of 'Anna Karenina' and I went, 'OK, I really need to not do anything dark for a while because the characters I've been playing for the last five years keep dying," she told Glamour. "It's been all death and destruction,'".

Jack Ryan: Shadow Recruit" is based on the Tom Clancy's iconic spy, Jack Ryan. Knightley plays Dr. Cathy Muller, Jack Ryan's future wife. Chris Pine  from the "Star Trek" reboot, stars as Jack.

The film also stars Kevin Costner as Ryan's boss, Thomas Harper, and Kenneth Branagh who directed the film and plays Victor Cherevin.

Knightley said she jumped on "Jack Ryan" for the chance to work with Branagh. Branagh is best known for his diverse films "Dead Again," "Sleuth"), "Mary Shelly's Frankenstein," and "Thor."

Knightley says it was Branagh's Shakespeare movie adaptations thrilled her. Knightley said "'Much Ado About Nothing,' 'Henry V,' and 'Hamlet' were such massive parts of why I wanted to be an actress. I wore out my VHS copy of 'Much Ado About Nothing' because I watched it so many times, so actually getting to work with him as an actor and director is amazing. It's fascinating watching him do his actor-director bit. One minute you're playing a scene with him, then all of a sudden he's running around the camera directing. It's really interesting watching him snap back-and-forth and watching him work. It's been a privilege."