Won an Academy Award for Best Supporting Actress for her role in the 2017 film I, Tonya. She played C.J. Cregg on the show The West Wing and began starring in the show Mom in 2013. Other memorable roles include The Duff, Hairspray, Juno, American Beauty, Spy and The Help.
She wanted to become a professional ice skater. She later would lie about being a photographer to cover up her failure at breaking into the acting business.
She has two brothers named Hal and Jay. In 2012 she entered into a relationship with Philip Joncas.
She played Brenda in the film Juno alongside fellow cast member Michael Cera.