Colonia begins in 1973 Santiago de Chile, where its citizens are lining the streets to support socialist President Salvador Allende as his cavalcade makes its way past. The footage is real, and the newscast warns of possible civil war in Chile, with the Soviet Union supporting the country while the United States regards Allende as a Communist who must be removed.

The chances seem somewhat slim, though, that this tape of political upheaval was ever accompanied by Bill Withers’ “Ain’t No Sunshine,” as it is in the movie.

That’s the first bit of weirdness in Florian Gallenberger’s often-creepy romantic drama, which doesn’t waste much time bringing Chilean dictator Augusto Pinochet into power. This coup d’etat immediately endangers Daniel (Daniel Brühl), a recent transplant from Germany who nonetheless becomes active among Allende supporters, taking photographs and drawing posters for the cause. Therefore his girlfriend, Lena (Emma Watson), is at risk, too, having picked a seriously bad time to stay with Daniel for a few days during her layover as a flight attendant.

When running outside amidst the chaos of Pinochet’s goons beating and arresting alleged Allende supporters, Daniel makes the dumb move of taking photos at hip level even though the couple had made it past the worst area. This gets him noticed, and once he’s affirmed as an activist for the deposed, Daniel is taken to the ironically named Colonia Dignidad—or “Colony of Dignity,” an isolated religious community where, under an agreement with Pinochet, the arrested are sent to be tortured. Lena decides to join the group to find Daniel, putting on her Sunday worst and quickly responding to the gatekeeper’s “God bless” with the same.

Lena’s bag, including her passport, is immediately tossed by Gisela (Richenda Carey), who might best be described as a cult mother to the female residents. But the true, maniacal leader with a God complex is Paul Schäfer (Michael Nyqvist), who immediately puts Lena in the hot seat and accuses her of lying about not having a boyfriend: “I can see it in your eyes. I can see it in your soul.”

After some icky and indirect threats from Schäfer, Lena is taken to her multibed room by Gisela, who points to her new basket of stuff (“Use the bandage to tie down your breasts”), and later spends time working the fields while Mother watches them with a whip. The men, women, and children are separated and not allowed to interact, throwing a wrench in Lena’s plans. Another wrench: Schäfer’s casual statement that “once you join us, you must remain.”

Gallenberger, who co-wrote the script with Torsten Wenzel, then makes an even stranger decision than using an R&B song of romantic lament to open the film: Though these prisoners are German and Chilean, everybody speaks English. Even the gate’s “Keep Out” sign is in English. I’m pretty sure this happened pre-Rosetta Stone and before English became a lingua franca.

Regardless, Colonia is an effective thriller, not only in terms of how Leah will find Daniel (who smartly uses a ruse to be largely left alone), but also because of its peek into the horrors of physical and psychological torture in the name of God. Nyqvist is the standout here, with long, greasy gray hair while lending Schäfer a disturbingly calm demeanor that everyone knows hides an explosiveness underneath. Brühl is magnetic as his Daniel is ever-watchful yet intensely in his head. Watson, however, has little to do but scowl, look serious, and be scowling-ly serious while Lena observes what’s going on around her; to her credit, though, her same-y expressions do give Lena a certain ferocity.

It’s also refreshing that, for once, it’s not the damsel who’s in distress. But said damsel, as well as her co-stars, needed to speak a smatter of Spanish or German for Colonia to be completely believable.

Colonia opens Friday at the Angelika Pop-Up.