Picking up exactly where Neil Marshall's chilling original left off, this bigger looking but less frightening companion piece is directed by Jon Harris, editor on The Descent. Emerging from the Appalachian mountain caves where she confronted her darkest dreads, traumatised Sarah Carter (Shauna Macdonald) is forced back into the subterranean depths by a suspicious police force that wants her help in locating her five missing girlfriends. Unlike Sarah, who gradually regains her memory and realises how futile the mission is, the rescue party has no idea what horrors lies in store as it enters the domain of a new breed of vicious "crawlers". The plot is heavily contrived and anyone who has seen the first film will find their familiarity with the claustrophobic atmosphere and sudden scares diminishes the overall nightmare impact. Yet Harris's direction is efficient enough, with some well-staged action highlights featuring all the required cliff-hanging, rock falls and underwater scenes.

Distraught, confused, and half-wild with fear, Sarah Carter emerges alone from the Appalachian cave system where she encountered unspeakable terrors. Unable to plausibly explain to the authorities what happened - or why she's covered in her friends' blood - Sarah is forced back to the subterranean depths to help locate her five missing companions.