Red Lights (2004)

This French film while well-photographed and well-directed by Cedric Kahn, struck me as something of a cheat.  The story just didn't ring true, and after the event I wonder whether the viewer was really meant to accept the tale as presented; there were just too many loose ends that didn't mesh.  We have a rather plain and not too confident man with an attractive, high-flying lawyer wife.  One Friday afternoon they set off from Paris to collect their children from a summer camp near Bordeaux.  He has fortified himself with several drinks before starting and stops at two further bars for a top-up.  When he returns to his car he finds a note from his wife saying that she will take the train.  There follows a nightmarish journey as he tries to find his wife, during which he picks up an escaped criminal who tests his mettle as a man.  He eventually finds his wife in a hospital -- she has been attacked by his passenger earlier in the evening.  If in fact he has killed the escapee as we are led to believe,why do the local police not find supporting evidence? And why does it all end up as "happy families" when it is pretty clear that his wife can't really stand him?