Time Out says
This 3-D cave-diving adventure plays on a lot of fears, so avoid it if you have an aversion to claustrophobia, drowning or really bad acting. A trapped group of adventurers must face some merciless challenges---rocky obstructions, torrential waterways, dreadful dialogue---as they reenact The Poseidon Adventure in a labyrinthine South Pacific cavern. Director Alister Grierson knows his way around action scenes (the film bears James Cameron's executive-producer seal of approval), but when it comes to performances, he's a squirm-inducing amateur. Worst in show: the Razzie-worthy Gruffudd as the expedition's hysteria-prone financier. Where's Paul Reiser when you need him?
Watch the trailer