Sanctum is simply one of the best types of man versus nature movie ever made. It’s an instant classic. That being said, Sanctum works so well because the conflict, the villain of the piece revolves around everyday if not experienced spelunkers trying to outwit a series of natural disasters.
First there’s a cyclone that all but obliterates the terrestrial base camp at cave Esa Ala (located in Papua New Guinea). The entrance to the cave is a vertical drop that’s so deep the really adventurous use a parachute to get to the bottom of the first level. The storm precedes a breakdown and cave-in of many of the subterranean caverns, both explored and unexplored, which form the Esa Ala system. Perhaps not oddly, the film was lensed in Queensland, Australia, and even as I write this that coastal section of Queensland is being buffeted by the biggest cyclone (Yazi) in their history.
Sanctum starts off innocently enough as we’re introduced to a bunch of really different characters: at the end of the explored section of Esa Ala is a team headed by Frank (Richard Roxburgh, practically the spiritual center of the film) and we’re informed through dialogue that he’s the world’s greatest cave explorer. Other characters include several spelunkers with various skill sets; the billionaire that has funded this venture, himself a bit reckless (Carl played with a hint of cowardice by Ioan Gruffudd), along with his less-than-experienced girlfriend whom he met in the Himalayas (Alice Parkinson); and of course Frank’s estranged son. A cave-in separates the core characters from the rest of the people involved with the expedition.
While James Cameron’s name places prominent in the ads he’s really only the executive producer along with the co-inventor of the 3D camera system used to film Sanctum. It’s really newbie director Alister Grierson that keeps the suspense at nail biting levels for the duration of the film as well as finding impossible angles to convey the extreme danger of the situation. The 3D lensing takes care to establish both depth and conversely a shallow sense of claustrophobia.
One by one the survivors get knocked off due to everything from rising water to inexperience. When only a handful are left it becomes apparent they will have to traverse the unknown section of the cave that leads to the sea, mostly underwater with very little in the way of oxygen or light. Sanctum is the kind of movie that just hands you your breath on a silver platter.
— Michael Bergeron