The pleasure of a whodunit generally derives from trying to figure out who done it, but in the case of this arty, terminally obscure French mystery, most of the story has already transpired before one can even piece together what was done. Mathieu Amalric, who also wrote and directed, stars as a middle-class husband and father who has drifted into a sweaty yearlong affair with a pharmacist’s unhappy wife, played by Stéphanie Cléau; scenes of Amalric’s character being interrogated by police frame a series of flashbacks that gradually reveal the crime and possibly the culprit. To judge from the opening shot, the title refers to the bedchamber where the adulterous couple meet for their heavy-breathing trysts, but to judge from the closing one, it’s really the court chamber where they stand trial together for murder. Perhaps the whole movie would be clearer if you watched it in reverse. In French with subtitles.