S1, E1: It's 1975, and two tennis greats, Billie Jean King and Arthur Ashe, are aiming to win Wimbledon titles but also, in their own ways, to change the world for the better. Having dominated the women's game, winning several Wimbledons, King is spearheading the drive for equal prize money and equal treatment of women, whilst Ashe focuses his attention on racial equality on and off the court.