Baryshnikov began acting at age 6 in a children's theater production of A Midsummer Night's Dream, portraying Peaseblossom, a handmaiden to fairy queen Titania. After graduating from Northwestern University in 2014, she began acting professionally on various television series, including Doll & Em on HBO. Her parents were initially hesitant about her career choice before becoming supportive.
Baryshnikov's most prominent role to date was in the 2016 critically acclaimed drama Manchester by the Sea, alongside Casey Affleck and Michelle Williams. Her character, Sandy, is a girlfriend of Patrick Chandler, portrayed by Lucas Hedges. She perfected a Boston accent by working with a dialect coach and going to Boston-area malls to hear how local teenage girls really spoke.
In 2017, she appeared in the Broadway production of the play Time and the Conways.
