If it weren’t for the poster and trailer — and in fact, this review — you’d be forgiven for thinking 1BR was a Millennial white collar romance from the first third of the film. But somehow this mix of Hot Fuzz and Rosemary’s Baby doesn’t lag even a bit as it winds its way from the dread of a life at a dead-end job to full-out apartment horror. And even once it announces its genre, it is still full of surprises.

There is, in LA, a happy, golden-auraed community in a gated apartment complex, and Sarah (Nicole Brydon Bloom) show up at an open house, looking for a simple one-bedroom apartment she can afford on a temp secretary’s wages while she goes to school and pursues a career in costuming.

The manager Jerry (Taylor Nichols) introduces himself and invites her to apply, and even though it is smoke-free and pet-free, Sarah lies about her cat and gets the apartment. Her new neighbors, including the hunky Brian (Giles Matthey) and the doddery ex-actress Miss Stanhope (Susan Davis) show her around, introducing her to the community at a barbecue attended by every tennant. “We all kind of take care of each other here,” says Brian.

When asked why she wanted to move, Sarah answers, “I guess I’m trying to start a new life.”

On the periphery of the party is Lester (Clayton Hoff) with one lens of his glasses blacked out, nervous, out of place. He offers Sarah a book (The Power of Community book by Charles D. Ellerby PhD), saying it changed his life, but she declines.

The first sign that all is not as idyllic as it seems is innocuous enough: after dark, the plumbing bangs and groans, keeping Sarah awake night after night, to the point where her cool coworker Lisa (Celeste Sully) comments on how worn down she’s looking.

And someone in the complex knows about her cat, and leaves an angry note under her door: “SOME PEOPLE ARE ALLERGIC, YOU SELFISH BITCH!”

Selfishness is not a trait the community favors, apparently.

This movie is well-paced, and moves forward well even when not much is happening aside from introductions. Characters are believable and well-acted, even before they’re fleshed out.

Sarah does sleepy paranoia well, and soon the moment comes when a horrific scene escalates the film from dread to actual peril, abduction, torture and reveals itself as a finely-crafted psychological thriller.