Kate Rooney Mara (born February 27, 1983) is an American actress. She is known for her work in television, playing reporter Zoe Barnes in the Netflix political drama House of Cards (2013–2014; 2016), computer analyst Shari Rothenberg in the Fox thriller series 24 (2006), wronged mistress Hayden McClaine in the FX miniseries American Horror Story: Murder House (2011), Patty Bowes in the first season of the FX drag ball culture drama series Pose (2018), and a teacher who begins an illicit relationship with an underage student in the FX miniseries A Teacher (2020). For the latter, she received an Independent Spirit Award nomination for Best New Scripted Series as an executive producer.

Mara made her film debut in Random Hearts(1999). She has since appeared in Brokeback Mountain (2005), We Are Marshall (2006), Shooter (2007), Transsiberian (2008), Stone of Destiny (2008), The Open Road (2009), Transcendence (2014), The Martian (2015), Fantastic Four (2015), Morgan (2016), Megan Leavey (2017), My Days of Mercy (2017), and Chappaquiddick (2018).