It's obvious very quickly into Red Lights that things are coming to a head.  Antoine (Jean-Pierre Darroussin, The Landlords, A Private Affair) and Helene (Carole Bouquet, The Bridge, Lucie Aubrac) are a married couple ready to make the long car trip to pick up their kids from camp, and Helene is late.  Traffic is looking to be horrible, so Antoine stops by a bar and has a few drinks.  Once Helene finally arrives, they decide to stay home and start later once traffic dies down.  Antoine skips out and has another drink.  By the time they are actually on the road, they are both tense, argumentative, and tired, and Antoine decides to stop a few more times for drinks (although he gives Helene other excuses).

At one point Helene tells Antoine that if he leaves the car, she will continue on without him.  Drunk and pissed, Antoine goes into the bar.  By the time he comes out, Helene is gone.  And so begins Red Lights, the new film by Cedric Kahn (Roberto Succo, L'Ennui), based on the novel by Georges Simeon.  Antoine finally realizes what a jerk he's been, and now must try to find his wife.  Traffic is still snarled, it's now night, and worse, a murderer is on the loose.  And Antoine is still drunk, so his mental capability is not at his fullest.  Because of this, he still acts recklessly, especially on the road, and makes some pretty rash decisions.

Kahn, who co-wrote with Laurence Ferreira Barbosa (Modern Life, L'Ennui) and Gilles Marchand (Bon Voyage, With a Friend Like Harry) keep the tension high by having Antoine's state of drunkenness constantly come into play.  Antoine has no idea what happened to his wife.  As far as he can tell, Helene just disappeared.  If he were sober, he could probably figure things out quicker, but nothing makes sense.  The fact that a murderer is running free only increases his anxiety, and the ever-present traffic only adds to his annoyance.  To make things even worse, Antoine keeps making the wrong decisions.  It's excruciatingly painful for people to watch him do stupid things, and this is exactly what Kahn wants.

Darroussin is perfect as Antoine.  He has a cracked, grizzled face that does not tilt lightly towards humor.  It's very easy for him to look pissed off, and he pulls it off for most of the film.  He actually looks like he is getting more drunk as Red Lights progresses.  His speech slows down, and more importantly, his gait changes.  Amazingly, even after he knows his wife is missing, and after he begins his search for her, he still stops into a bar or two for a drink.  Kahn squeezes the maximum amount of tension out of every situation, making an ordinary police stop seem like a life or death situation.  Even when things come into the clear near the end, Kahn still milks out the amount of time before providing explanations, keeping the uneasy, off-balance tone of the film.  Kahn is clearly manipulating the audience to make them feel uncomfortable, but it works.