The 29-year-old walked the red carpet at the Hollywood Palladium clad in a rather ethereal looking Deplozo gown that trailed behind for quite some bit.
Let's hope no one stood on that train!
Keira is expecting her first child with musician husband James Righton, 31, but any sign of a blossoming baby bump was firmly covered by the fit of her dress, as has been her style this awards season.
Klaxons star James accompanied Keira to the Critics' Choice Movie Awards, where she was nominated in the 'Best Supporting Actress' category for her role in the Alan Turning movie The Imitation Game.
She lost out to Patricia Arquette in Boyhood.
Keira's appearance on the red carpet came the same day she learned she'd also been nominated for an Oscar for her performance in The Imitation Game.
After learning of the news, she said: "What an exciting morning! I'm so honoured and grateful for this nomination and to be in the company of such talented and inspiring actresses. Thank you to the Academy for this recognition and also for honouring so many of the film's storytellers. I would like to think the many recognitions the Academy has given our movie is a celebration of Alan Turing's legacy."
Her co-star Benedict Cumberbatch has been nominated in the 'Best Actor' category, while the movie is up for a slew of other awards including 'Best Picture'.
The Oscars take place in LA on 22 February.