Actress who played bad girl Jennifer Lindley on the television series Dawson's Creek, then went on to star in such movies as Blue Valentine, I'm Not There, Synecdoche, New York and Manchester by the Sea. Her portrayal of Marilyn Monroe in the 2011 film My Week with Marilyn earned her a multitude of awards, including a Golden Globe Award for Best Actress.
She won an Independent Spirit Award for Best Supporting Female for her role as Alma Beers del Mar in the 2005 film Brokeback Mountain.
She and then-boyfriend, Heath Ledger welcomed a daughter, Matilda Ledger, in October of 2005. They split in September of 2007, four months prior to his death. She had relationships with Spike Jonze, Cary Fukunaga, Jason Segel, Andrew Yumans and Jonathan Safran Foer. In 2018, she married Phil Elverum, but the two separated in 2019. Williams and her husband Thomas Kail welcomed their first child together in June 2020.