After a teenage boy dies in a meth lab explosion, his inspirational head-teacher, Noah Taylor, resolves to confront the drug dealers preying on his community. Dangerous batches of new drugs are hitting the streets and its down to Nikki, Jack, Clarissa and Thomas to deal with the consequent rise in overdoses. When tragedy strikes at the heart of the Taylor family, it puts Noah on a collision course with the criminals behind the drugs.

A collection of dismembered body parts, covered in intricate Japanese tattoos, have been found in a Brighton waste dump. The team are called in to painstakingly piece them together and they search for clues to lead them to the killer. Outside of the lab, Nikki has some news she desperately wants to share with Matt.