Rose to fame with her starring role as Lindsay Weir on Freaks and Geeks. Her other notable TV credits include ER, Bloodline and later Dead To Me. She's had prominent roles in films such as Green Book and Daddy's Home as well as supporting roles in Grandma's Boy, Good Burger, Legally Blonde and Brokeback Mountain.
She had her first acting role in the 1996 children's show Bone Chillers.
She had her first daughter, Lilah-Rose, with longtime boyfriend Steven Rodriguez in February 2012. The couple became engaged in 2013. She was previously in a five-year-long relationship with Jason Segel.
She acted alongside Freddie Prinze Jr. in the Scooby-Doo live-action films.