The Descent's director Neil Marshall and producer Christian Colson will produce the sequel for UK-based production outfit Celador.
Jon Harris, who edited The Descent as well as Stardust and Layer Cake, will make his directorial debut with the project. He is also editing Pathe/Celador project Eden Lake directed by James Watkins, who in turn is writing the screenplay for The Descent 2.
The film will set to shoot starting in mid-April with a likely first-quarter 2009 UK theatrical release (through Pathe Distribution.)
Pathe also worked on 2005's The Descent, which went on to earn more than $57m worldwide after being made for just £3.5m. That film followed a group of girlfriends who encounter a creature on a caving trip.
The storyline for the sequel is under wraps for now.
Pathe's slate also includes Saul Dibb's The Duchess, Christophe Barratier's Paris 36, Danny Boyle's Slumdog Millionaire, Paul Andrew Williams' The Cottage and Jane Campion's Keats project Bright Star.