If you’re a woman in a horror movie, yours is often a lonely existence. If you haven’t been hacked to pieces or eaten before the end of the movie, you’re probably the lone survivor of the killer’s rampage. Whether you climb into the back of a conveniently passing pickup truck, float out into the middle of the lake in a canoe or get saved at the last minute by Donald Pleasance, you’re the Final Girl. Your friends are all dead, and you have to make it through the last act of the movie all by yourself. Being a woman in a horror movie usually means you either become self-reliant, find a man to save you, or you die.

That’s a big part of the reason why I found “Patchwork” to be so refreshing, because it’s one of the rare horror movies I’ve seen where the focus is on the relationships between women. Even if it’s not entirely successful in that regard, it’s at least attempting something different. Rather than make its lead characters stronger by isolating them, “Patchwork” focuses on its women surviving by getting closer together. You literally can’t get any closer together than the women of “Patchwork” do, as a matter of fact.

Jennifer is an aggressive, career-focused woman who’s in a lopsided relationship with her married boss. Ellie is a ditzy, awkward party girl who spends a lot of time going to bars by herself. Madeleine is a shy, insecure loner who obsesses about improving her plain appearance. One thing they all have in common is that they’re all lonely and starved for any kind of attention, male or female. Another thing they have in common is that they’re all chopped up and sewn together into a single body, and they’re not very happy about it.

True to its name, the narrative of “Patchwork” skips and jumps around between the aftermath of these women being amalgamated into a Frankenstein monster and their lives just before it happened. After the initial shock of what’s happened to them wears off and they escape from the dingy back-alley laboratory, the women set out to get revenge on the people who did this to them as well as anyone else who may have victimized them. They quickly rack up a body count that includes Jennifer’s three-timing boss, a pack of frat boys who took advantage of Ellie and some of the black-market surgeons who made them the way they are. Everything escalates to the point at which the Frankenwomen confront the mad scientist behind it all while dealing with an internal conflict over how far they’re willing to go.

I’m not smart enough or qualified to say much about the gender politics of this movie, except to say they exist. A big part of this movie is about the way men treat women and how that influences the way women treat each other. But instead of positioning their revenge as simply getting even with men for mistreating them, “Patchwork” makes it more about the way these three women make each other stronger. In fact, the movie depicts their becoming a Frankenstein as something liberating. The everyday humiliations and anxieties they suffer before they’re sewn together come across as more traumatic than the experience of being hacked apart and reassembled by a mad scientist.

As a horror-comedy, “Patchwork” owes a debt to horror movies with a sense of humor like “Re-Animator,” and Stuart Gordon gets a shout-out in the credits in case the connection is lost on anyone. If anything, it could have benefited from a bit more gore, and the frathouse assault the ladies wage especially feels like a lost opportunity for some good old-fashioned splatter. But the movie’s bouncy energy and a well-timed twist keep it from getting stale even when there’s no blood being spilled.

So many horror movies present female empowerment coming out of victimization, but “Patchwork” is the rare example of women finding strength in each other rather than being forced to survive alone. For the women of “Patchwork,” becoming the monster is the best way to prevent becoming the victim.