Billie Jean King campaigned for equal pay in professional tennis. Ironically, Hollywood is one of the worst offenders when it comes to pay inequality.
Like a tennis player who can't find the lines, Battle of the Sexes bounces around all over the show, never quite hitting its mark.
Emma Stone is excellent as 1970s tennis champion Billie Jean King, who took on the big boys of United States Lawn Tennis Association in a bid to get equal pay and prize money for female players.
Together with World Tennis founder Gladys Heldman, played with fabulous panache by Sarah Silverman, King and seven other players quit the USLTA to form their own tennis tour, offering more than triple the prize money of their rivals.
Similar to A League of their Own, it's an inspirational watch as the women combine their feminine wiles with sheer bloody-mindedness to forge a new path and fight for gender equality.
While some moments are so 70s kitsch - like bringing fashion designer Ted Tinling on tour to create custom outfits for the ladies - it's hard to believe they happened (they did), others are still all-too-familiar in 2017.
If you've seen the trailer for the film, you might be wondering where Steve Carrell comes into things. In fact, it's only in the second half of the film that he really becomes part of the story, playing former tennis champ and gambling addict Bobby Riggs.
A consummate hustler, 55-year-old Riggs sees the opportunity for the ultimate publicity stunt, offering King $100,000 if she can beat him in three sets.
The rest of the film builds up to this historic match, which was dubbed Battle of the Sexes and watched by more than 90 million people worldwide.
Along the way, the film visits both King and Riggs' personal lives - as she explores her sexuality and his marriage breaks down - but so lightly that they only act to slow proceedings.
Likewise, the film hints at other stories - like Australian Margaret Court's homophobic religious beliefs - without confronting them directly.
Peppered with slapstick comedy and moments of genuine inspiration, the story is let down by these time-consuming detours, which do nothing to progress the central story and leave you itching to Google what really happened.
Cast: Emma Stone, Steve Carrell, Sarah Silverman Director: Jonathon Dayton and Valerie Faris Running time: 121 mins Rating: M Verdict: Not quite an ace.
DID YOU KNOW...
When filming the original Kingsman: The Secret Service film a technical error saw the set flooded with water, leaving cast and crew struggling to escape the deluge. The scene was included in the final cut, with director Matthew Vaughn saying: "Those actors weren't acting, they were absolutely terrified."