A by-the-numbers submarine pic which steals its every idea and re-floats the usual stuff about a missing craft, a government conspiracy, an on-board saboteur (Alien), and a big mother of a monster (Aliens). The captain (Ermey) is a hardass, the crew is multi-ethnic, and the hero's estranged wife is on board (The Abyss) to up the tension level. When Siren One, a state-of-the-art nuclear sub, goes missing at a depth of 27,000 feet, the vessel's hunky designer (Scalia) joins a NATO team sent down to investigate. Tracking a 'black box' signal to the deep Dannekin rift, the crew discovers a vast underwater cavern populated by mutant life forms, apparently the result of some secret government experiments in gene splicing and accelerated evolution. Pretty soon, the seaweed hits the fan, and the crew are faced by monsters without and an enemy within. The wooden characterisations are predictably shallow, but the dodgy monster effects and model work plumb new depths of ineptitude.