In the wake of the sexual revolution and the rise of the women’s movement, Billie Jean King’s (Stone) triumph at the 1972 US Open is overshadowed by the National Tennis League’s decision to refuse equal pay for men and women. In an act of rebellion, King launches the Women’s Tennis Association, designed to provide a more equal working environment for female tennis players. This irks the misogynistic ex-pro Bobby Riggs (Carrell), who challenges her to the ultimate test, a match between the pair that will, in his mind, prove that women are lesser players than men.