Martin, the sole eyewitness in the murder case, is found dead in suspicious circumstances. Threatened by an angry Bekir, Nuri grows increasingly desperate to find the missing drugs, with tragic consequences. Nikki helps grieving William come to terms with his daughter Alice's death and his missing baby granddaughter.

Under pressure from his wife Ellie, DI John Brooke finally comes face-to-face with his nemesis, drug dealer Bekir. However, Jack's growing frustration over DI Brooke's meddling in the case unearths a new line of enquiry.

Jack's world is blown apart by the discovery of Hannah's dead body. Nikki uncovers the truth behind Jack and Ryan's strained relationship, but Jack's attempts to find evidence put his job at risk. While an angry Thomas wrestles with hiring forensic scientist Helen as Jack's permanent replacement, Dr Christy Nash fears for his marriage and business when DI Carter learns of his relationship with 15-year-old Katie. As Jack's suspicion of Ryan grows, his lone investigation puts him in grave danger and life will never be the same again.