Sudden death among the young, callow set

For all of its rigor, “One to Another” is so subtle that on the surface it seems like lots of other French films dealing with aimless youth who possess a veneer of sophistication concealing a dangerous naiveté.

While this certainly describes the five central figures of Pascal Arnold and Jean-Marc Barr’s elegantly unsettling film, what sets it apart is all that’s so effectively left unsaid -- that these affluent, attractive young people have grown up without any traditional notions of right and wrong.

The film’s beautiful setting is Aix-en-Provence and its surrounding countryside in the south of France.

It’s summertime, and Lucie (Lizzie Brocheré, a remarkably focused young actress) and her brother Pierre (Arthur Dupont) and their friends since childhood, Nicolas (Guillaume Baché), Sébastien (Pierre Perrier) and Baptiste (Nicolas Nollet), all of whom apparently have completed at least one year of college, have formed their own band, playing local gigs.

Saucy and vibrant Lucie and Pierre, too handsome for his own good, are the magnets of the group, and they know it. They have an unabashed, uninhibited love for each other that’s intensely physical, deeply emotional and seemingly inescapably incestuous -- but to what degree the siblings cloak in a teasing ambiguity.

Currently, Pierre’s having an affair with Nicolas, and Lucie is having one with Sébastien. At one point, the siblings are accused of using people; certainly, they are always in charge, and clearly the siblings don’t take their affairs seriously, which may not be the case with their partners. The five -- Baptiste seems to be the voyeur in this ménage á cinque -- spend most of their time together, often swimming and sunbathing in the nude.

“One to Another” unfolds as a recollection on the part of Lucie, a shrewd and forceful individual, proving to be strong and determined when tested. She and Pierre are highly articulate and reflective. Pierre reveals his self-knowledge when he tells Lucie that he’s not engaged in words or ideas but with his body. His friends may not be so self-aware or so self-confident but it can be said that at the outset of the film all five are more adept at using their bodies than their minds.

Early on, the summer’s idyll is shattered when Pierre takes off on his motorcycle and disappears. Eventually, his brutally beaten body is discovered and a police investigation concludes that he was probably the victim of out-of-towners.

Not satisfied, Lucie starts investigating. The way in which Arnold and Barr -- they co-direct, with Arnold writing and Barr, the French-American actor, handling the camera -- unfold Lucie’s story and her eventual discovery may be shocking, but upon the reflection that the filmmakers inspire, unsurprising.

“One to Another.” Unrated. In French with English subtitles. Running time: 1 hour, 35 minutes. At Laemmle’s Sunset 5, 8000 Sunset Blvd. (323) 848-3500.