The Descent is a 2005 British horror film written and directed by Neil Marshall. The film follows six women who, having entered an unmapped cave system, become trapped, and are hunted by subterranean flesh-eating humanoids. Filming took place in the United Kingdom; exterior scenes were filmed at Ashridge Park, in Buckinghamshire, and interior scenes were filmed in sets built at Pinewood Studios near London. Filmmakers considered it too dangerous and time-consuming to shoot in an actual cave, and the cave featured in the film was built at the studio. The Descent opened commercially 8 July 2005 in the United Kingdom. It premiered in the 2006 Sundance Film Festival and opened commercially on 4 August 2006 in the United States.