Katherine Boyer Waterston (born March 3, 1980) is a British-American actress and daughter of veteran actor Sam Waterston. She made her feature film debut in Michael Clayton (2007). She had supporting roles in films including Robot & Frank, Being Flynn (both 2012) and The Disappearance of Eleanor Rigby (2013), before her breakthrough performance in Inherent Vice (2014). She portrayed Chrisann Brennan in Steve Jobs (2015), and went on to star in Fantastic Beasts and Where to Find Them (2016) and its sequels. Her other film roles were in Alien: Covenant (2017), Logan Lucky (2017), The Current War (2017), Mid90s (2018) and The World to Come (2020).

Filmography