I found out about last Saturday’s season-closing bout between the Mission City Brawlin’ Betties and the West Coast Derby Knockouts entirely by chance. At dinner with a VP at Citrix, she casually mentioned that a few of her coworkers would be participating in a roller derby bout the next day. I assumed that this sport had died out in the 1970s and now existed only as basically a glorified form of female pro wrestling on ESPN Classic at 3 a.m. I was dead wrong, as evidenced by the throng gathered at the Earl Warren Showgrounds for the 5 p.m. bout between the two putative teams (this was the Brawlin’ Betties’ last bout of its inaugural season, and the first game for the Derby Knockouts), as well as the copious signage that ringed the roller rink.

It’s easy to see why such a crowd gathered: the sport is fast, fun, exciting to watch and — this is key — only $5 for roughly two-and-a-half-hours-worth of entertainment. For those of you who don’t know (and judging by the crowd, I’m guessing this is all of you), roller derby is played on an oval track between two teams of women. There are 10 women on the rink at once, and almost an equal number of referees, whose presence is necessary to keep track of the simple but mind-bogglingly complex-to-calculate scoring system. The points are scored by “jammers” — you can tell who they are because they wear a panty with a star on it on top of their helmet — who get points for every member of the other team that they lap during the two-minute “jam.” The other members of the team work furiously to prevent this from happening (the only rules are against elbowing, shoving from behind, and intentionally falling in front of a skater). The jam can be called off at any time by the lead jammer, which is a neat bit of strategy employed to keep the other team from racking up points if the jammer seems to be, um, jammed.

Basically, two women skate as fast as they can through a group of eight other women, four of whom are dedicated to severely injuring them, and the other four of whom are dedicated to preventing such a calamity.

The action is both fast and furious, and initially makes less than no sense. You come for the names (my highlights: “Booty Ninja,” “Stella Ar-twat” and the terrifying “Lady Destroyer”) but stay for Mary J. Yma (number 420 on the Betties) and Viva Violence (number -1) slicing up the opposing defense like a white, female LeBron James. On roller skates. In fishnets. I know.

Eventually, as you start to gravitate towards the front of the crowd, you start to notice things, like, say, the actual rules of the game. Or the Derby Knockouts’ female assistant coach frantically making the “suck it” gesture and screaming after a particularly vicious body block sent one of the Betties flying.

The Brawlin’ Betties romped throughout the bout, racking up almost 200 points and holding the Derby Knockouts to under 50 in a smackdown that seemed to be equal parts offense (Violence and Yma dominated the first half, and the Betties were able to turn to their 3rd-string jammer, Vino Noir, in the second to wrap up the game) and defense (the Derby Knockouts’ jammers were too slow, and the Betties, including the very appropriately named Booty Ninja, held them back behind a formidable wall). I have no grasp of the subtleties of the sport, but what I do grasp is that it’s an awesome experience that I couldn’t believe that I was seeing live. The women never seem to let up as they fly around the track, and on more than a few occasions I winced after a particularly brutal body block. Also, Someone Who Knows tells me that this was an abnormally quiet bout, and normally they get much rougher. If it were possible to buy season tickets to this, I would do it in a New York minute.

As it is, I’ll have to settle for finding every roller derby bout that I can and happily spending evenings under the bright lights, watching some Brawlin’ Betties.