Some chick wearing a Star Trek themed leotard (you know, that episode where Spock heads to the new wave fitness planet to work on his pecs…oh wait, I made that up) finally achieves her goal of becoming a cover model for Cosmo. While this may strike some as shallow, it’s all about getting your foot in the door in the waiting room of your dreams (so to speak). Admittedly, her forward momentum hits a snag when she lies down in a tanning bed and flames start shooting everywhere, leaving her a crispy pile of goo.
Well, if you like aerobics performed to bouncy synth pop, supplemented with neon wrist warmers, this is the movie for you. In charge of the jiggle parade is Rhonda, who is also writing a fitness book on the side, which I hope is called "Spandexerity – The Art of Getting Limber Without Ruining a Perm". However, this dual career runs into some roadblocks when a psycho starts offing customers with a giant safety pin.
The aerobicising continues unabated as they drag off the body bags right in front of these fucks. I guess fitness is really important and shit, and you have songs like "Rockin’ Rock" to drown out your inner voice saying “GET THE FUCK OUT OF HERE! THERE’S A KILLER RUNNING LOOSE YOU FUCKING MEATHEAD!!!”. Rhonda finally starts getting worried about her business, stating that "half of my customers are being killed, and the other half are cancelling their memberships". However, the place is full, so she must be getting new signees from all of the publicity with the safety pin homicides. Whatever gets the heart rate up, I guess.
Various characters splurge forth interesting bits of women hating rhetoric at different points. One guy suggests that one of the female murder victims should’ve been raped beforehand, as her body was wasted. Rhonda tells co-worker Jaimie to stop showing off her tits and tight little ass to the customers. Mulleted beefcake Ted Prior (of Deadly Prey fame, the greatest Rambo rip-off ever foisted upon a incredulous viewing public) gets into it with a douchebag in a Porsche, resulting in some poseur martial artiness. This showcase of alpha maleisms earns him the hand of a lovely lass in a pink leotard. She ascends to sex bomb trophy status while a synth song proclaims “she’s a knockout! let her rock out!”, which pretty much sums up the depth of the film’s female characters.
A group of unruly “teens” later spray paint "aerobicide, death spa" on the window of Rhonda’s establishment. Apparently, street ruffians have nothing better to do than point out the similarities between this film (originally titled "Aerobicide") and the film Death Spa, which is pretty much Killer Workout, but with the sweat hogs getting offed by the actual workout equipment instead of a safety pin. The ruffians are thereby guilty of sullying the artistic integrity of the very film they find themselves in, so of course they are immediately murdered for their transgressions. Genius.
(spoilers here on out)
In the shocking twist, we learn that Rhonda is the tanning bed burn victim from the prologue. A copper shows up and confronts her about being a toasty killer disguised in a leotard, wig, and complex latex makeup. She admits it, and says she killed people because they're beautiful, despite the fact that she herself is pretty hot when made up all proper like. She then flashes her burnt titties and gets arrested. Oh how the tragedy unfolds.
In the end, I guess Rhonda has a love/hate relationship with her customers. She likes killing them off to feel better about being a crispy mess but, on the other hand, this aerobics craze really lets her rake in the cash. Luckily, she gets the best of both worlds, since she can kill off her customer base, and they just get replaced with fresh new bodies; that is, Stairmaster addicted, baby-boomer asshole sheep.