Moneyball is about Oakland A's general manager Billy Beane, and is based on the book by Michael Lewis. I read the book back in the mid-2000s when it came out and found it intriguing. I looked forward to the movie as a baseball fan, a movie fan, and a Brad Pitt fan. Needless to say with a Tomatometer reading of 95 percent I wasn't disappointed on any front.
What Billy Beane (Brad Pitt) did was unthinkable prior to 2002 because nobody would take the risk. He and his associates (a fictional composite in the movie, played by Jonah Hill) decided to use the overly geeky statistical analysis pioneered by overly geeky Bill James to fill up a ball club that had a very small payroll.
Among other things, they used something called On Base Percentage (OBP), which they believed meant more than the traditional intuition of scouts and baseball mythology, and perhaps even of such stats as RBIs and batting average. The theory goes: no matter how you got on base - you become a potential run. If you get on base more often than others - regardless of the reason, such as walking, you are more likely pretty valuable to a winning team - or even make your team a winning team.
That in a nutshell is the story; sounds dull and boring, doesn't it? On the other hand, it is a movie about the economics (dull) of baseball statistics (and boring)? But if you can get Brad Pitt to star, and Aaron Sorkin to be one of the screenwriters, you have a winner. (Kind of goes against the baseball premise, doesn't it?) It is not an action movie. Even the baseball scenes are there to carry the underlying story. (Although we do get to see the Minnesota Twins portrayed a couple times.)