As part of a drunken bet with her sister, a happily married woman sends an anonymous Valentine's card to her husband to see if he hides it. When he does, what was a prank leads to a series of events and revelations that puts her marriage at risk, and leaves her looking for revenge.

The Baseline is the centre of the East London grime club scene and the queue regularly stretches around the block. Danny works on the door - breaking up fights and managing drunk kids. However, when he rescues Terry, the club owner and local gang leader, from a hitman, Danny is suddenly plunged deep into an underworld he had tried so hard to avoid. Danny is promoted to manager, but only on the condition that he turns a blind eye to the shady goings on both on and off the dance-floor. Danny and his girlfriend Jessica dream of setting up their own club, but Danny is forced to make the ultimate sacrifice when he has to choose between loyalty, morality and his own dreams of escape.

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. As the rescue party drives deeper into uncharted caverns, nightmarish visions of the recent past begin to haunt Sarah and she starts to realize the full horror and futility of the mission. Subjected to the suspicion and mistrust of the group and confronted once more by the inbred, feral and savagely ruthless Crawlers, Sarah must draw on all her inner reserves of strength and courage in a desperate final struggle for deliverance and redemption.