The film will be directed by Alister Grierson. It was written by Andrew Wight and John Garvin.
Sanctum is a fictional film that was inspired by Wight's near-death experience when he took an expedition of 15 divers into a remote underwater cave system. It was below Australia's Nullarbor Plain and it was there that a storm blocked up the cave entrance. Wight and the expedition waged a two-day battle for survival and eventually all 15 were rescued.
This event was retold in the 1989 documentary Nullarbor Dreaming.
In the new film, a tough father and his son take charge of a diving team. The true colors of the team come out when they find their backs against the wall.
"As one who was nearly killed in that cave collapse, I thought there was great stuff in how people react in crisis, and become heroes or cowards," Wight said. "Jim and I spoke about all this while working on these 3D adventure projects, and we had a burning desire to make a gritty film about what it's like to be on an expedition and have it all go horribly wrong. We wanted to show that the 3D equipment and technology can be used to tell a story in a modest budget independent film."
The film will start shooting in Australia later this year.