Characters who are adrift and lonely in outer space? We’ve seen that movie plenty of times. But writer/director Claire Denis is nothing if not original, and her “High Life” offers this: an artificial insemination that involves sexually assaulting both the mother and the father.

If that sounds unpleasant, then you’re getting the idea about this movie, much of which is queasily difficult to watch, in a David Cronenberg/”Dead Ringers”/body horror way.

Denis, whose “Let the Sunshine In” was a hit at last year’s Minneapolis St. Paul International Film Festival, opens the film with the would-be bucolic image of a garden, but ominous music and the odd stickiness of the plant are clues that we’re not in paradise. We may, in fact, be in hell: a spacecraft where all the residents are murderers, Death Row inmates who are serving their sentences in the name of science. What could possibly go wrong?

The craft’s sole residents seem to be a baby girl named Willow and mysterious Monte (Robert Pattinson, who, like former co-star Kristen Stewart, has used the “Twilight” windfall as an opportunity to let his movie freak flag fly).

Soon, “High Life” shifts to extended flashbacks so we can meet other characters, including Juliette Binoche as a doctor whose bedside manner could best be described as “demonic,” and we learn how Monte and Willow ended up alone in space.

Many head-scratching things occur, but Denis’ calm approach indicates that what interests her is not outer space but how living in it might affect behavior. The movie spends most of its time with Monte, whose eerie resolve suggests either he has given up on life or he is prepared to survive by any means necessary.

It’s clear he loves Willow, but the general air of lawless amorality on board the ship hints that whatever rules killers followed when they were on Earth may not apply now that they’re on what might be a suicide mission.

Why, for instance, does Monte take care to teach baby Willow what a taboo is? And what do the specifics of the crime he committed say about his long-term viability in space?

Questions always linger after Denis’ elliptical movies, which include “White Material” and “Beau Travail” and which often have an allegorical feel. It’s possible that the spaceship is a metaphor for Earth and that we are the criminals who, having destroyed this planet, are on a desperate search for a new, unwrecked one.

We’ll need the insights of future generations like Willow’s if we are to survive, and, as “High Life” shifts from the past to the future of this man and girl, that’s the biggest question it asks: Can she save him? And us?