I usually enjoy submarine movies. Loads of action and precious little romance to clutter up the thing. On that front, this delivers quite well as Matthew McConaughey ("Tyler") and Bill Paxton ("Dahlgren") lead a daring mission to capture the enigma coding machine from an U-Boat. Thanks to a broken down Nazi sub in the middle of the ocean, the initial part of the operation goes surprisingly smoothly, but just at the moment of triumph, well - the rudder comes off. They must now make the best use they can of their captured ship and try to make it home in one piece with their prize. This isn't going to be easy. The torpedo tubes don't work. the thing is held together with chewing gum and willpower and the enemy know that they are out there. If you ignore the fact that this has very little to do with the history of the actual device, well, at least until the few captions at the end - this is quite a passable adventure with plenty of action, some not so great CGI and a competent acting ensemble to do the gung ho, ye ha stuff adequately enough. It can, at times, be effectively claustrophobic and does illustrate just how precarious life could be stuck in an airless tube 600 feet under the surface - especially when some guy on top is dropping depth charges. It's watchable, but equally forgettable.