Martin, age 20, runs away from his rural French home under mysterious circumstances and ends up at his half-brother's flat in Paris, where he meets and falls in love with the half-brother's female roommate Alice, age somewhat older. When Alice informs him, halfway through the film, that she is pregnant, he has a flashback (which we don't see for a while yet) of what happened to make him flee his father's house, and for the rest of the film, while Martin languishes in a psychiatric facility, Alice must resolve the situation Martin created, a labor of love she doesn't hesitate to perform even though it involves the sacrifice of her own happiness.
The bad news: This is a long, slow movie, and the characters are not really as well-defined as they perhaps could have been, especially given the film's character-centered plot. The good news: It's really beautiful to watch, and when the end of the movie sneaks up on you, and you've given what you've seen a little while to sink in, it's so brilliantly sad that you just want to fly to Paris and find Alice and hug her or take her to dinner or something. Not a good choice for a first-date movie--rent the video and have a close friend over for wine and cheese.