Kathryn Marie Hahn is an American actress and comedian. She began her career on television, starring as grief counselor Lily Lebowski in the NBC crime drama series Crossing Jordan (2001–2007). Hahn gained prominence appearing as a supporting actress in a number of comedy films, including How to Lose a Guy in 10 Days (2003), Anchorman: The Legend of Ron Burgundy (2004), Step Brothers (2008), The Goods: Live Hard, Sell Hard (2009), Our Idiot Brother (2011), We're the Millers and The Secret Life of Walter Mitty, and Glass Onion (2022).

Our Idiot Brother is a 2011 American comedy-drama film directed by Jesse Peretz and starring Paul Rudd, Elizabeth Banks, Zooey Deschanel and Emily Mortimer. The script was written by Evgenia Peretz and David Schisgall based on Jesse and Evgenia Peretz's story, and tells the story of a dimwitted but idealistic and well-meaning man who intrudes and wreaks havoc in his three sisters' lives.