Carol (Lake Bell) is an aspiring voiceover artist who’s grown up in the shadow of her father, Sam Soto (Fred Melamed), an industry icon. Sam belittles her career chances as a woman in the voiceover world, preferring to encourage male protégé Gustav (Ken Marino). She’s also at odds with her father for other reasons, resenting his young girlfriend Jamie (Alexandra Holden), who seems to represent the kind of ‘baby-voiced’ femininity Carol hates.
When Jamie moves in and Carol is kicked out of Sam’s house, she moves in with her sister Dani (Michaela Watkins) and brother-in-law Moe (Rob Corddry), who are going through a rough patch in their marriage. Trying to keep things together in her personal life whilst pushing ahead professionally, Carol must find a way to make her voice heard.
Richard (Joel Edgerton) and Mildred (Ruth Negga) are young, in love and expecting a baby. The year is 1958: because Richard is white and Mildred is black, a marriage between them will be illegal in their home state of Virginia. In order to get married, they will have to cross state lines.
After a small ceremony in Washington they return to live quietly in the town of Central Point. But though their own rural community is relatively integrated, the state authorities have got wind of their relationship, leading to the couple being arrested after a night-time raid on their home. In order to avoid prison time, they must accept a 25-year banishment from the state of Virginia, meaning a separation from family and friends.
As the years pass and their children grow up in the city, Mildred in particular misses her home, and begins to wonder if anything can be done to overturn the ruling. A phone call from the American Civil Liberties Union ignites her hope – setting this unassuming couple on the path to changing history.