An original approach to submarine thrillers that pits the best of the French nuclear submarine forces against shadowy adversaries that may or may not be who they seem. A very real threat of world-wide Armageddon caused by a rogue missile launch is captured in a realistic and believable plot with excellent acting all around and very convincing sets and surroundings. There are no recognizable stars for an American audience which allows viewers to concentrate on the story rather than personalities. Superb directing with top-notch support from the art department and special effects. Some effects are familiar to fans of modern submarine films and nothing really new is presented in this area, but it all works effectively. Inclusion of an Iranian Navy subplot sparks interest from the very beginning; this gradually blossoms into a much more deadly set of circumstances with some unexpected twists on the way. Overall, a richly satisfying production that I will happily watch again in the future, if only to catch details that I missed the first time.