The Girl with the Dragon Tattoo, right? Close – she's Dragon Tattoo star Rooney Mara's older sister
And she acts, too? She certainly does. Mara was in Harrison Ford's Random Hearts at 16 and has had TV roles in everything from Everwood to Nip/Tuck. After stealing the show in American Horror Story, she plays journalist Zoe Barnes in David Fincher's much-anticipated House of Cards remake.
Hang on. That David Fincher? Didn't he direct Rooney in The Social Network and Dragon Tattoo? Correct, and Kate says she owes the part in House of Cards to her little sis: "I fell in love with the character and asked Rooney to put in a word for me with Fincher. A month later I got a call to come and audition."
So she and Rooney are close, then? Very. The Maras are your typical Irish-American family: four kids, countless cousins, raucous holidays… Oh, and a couple of football franchises on the side – her mother's family founded the Pittsburgh Steelers, her father's family own the New York Giants.
She says: "I'm more relaxed these days. I worry less about the next step and don't stress so much about projects."
We say: Get set for a Mara v Mara Oscar showdown one day.
All 13 episodes of House of Cards are available on Netflix from 1 February