When a man is thrown from a high-rise building, the team are propelled into the criminal underworld of a notorious mafia group, the Ndrangheta. Aided by the National Crime Agency, Nikki and her team set about uncovering the truth. As they descend deeper into the murky depths of the investigation, Nikki soon finds herself caught in the mafia's web, with deadly consequences.

An abandoned lorry is found at a quarry with several dead and dying people in the back. Initially, it appears to be a classic sex trafficking story that Nikki and the police are all too familiar with, but it soon becomes clear that all is not as it seems. With the survivors refusing to speak, Nikki and the team must use their pathological and forensic skills to identify the deceased and piece together what happened.