All eight episodes of the BBC crime drama following an undercover team of law enforcers. After leading a botched drugs bust, HM Revenue and Customs officer Marcus 'Ash' Ashton (O.T. Fagbenle) is chosen to head the new top-secret law enforcement squad known as the UNIT (Undercover Narcotics Intelligence Team) and is tasked with taking down key members of the criminal underworld. While Ash uses his knowledge of the street to fulfill his long-time goal of capturing high-level crime bosses and drug dealers, the team close in on their top target, notorious crook Roach (Trevor Eve).

Horror sequel continuing the story of a group of ill-fated cavers. After Sarah Carter (Shauna MacDonald) is rescued from the Appalachian caves where several of her friends came to a bloody end, she is made to go back and help to try and find any remaining survivors. The local Sheriff (Gavan O'Herlihy) is not wholly convinced by Sarah's version of events or about what she claims she and her friends encountered in the caves and so pushes for the rescue expedition. It soon becomes clear, however, that every awful thing Sarah told him was true.