• Air date: 22 Feb '21 6 episodes
      The fourth season opens with the discovery of a dismembered body in a scrap metal yard, which the team believe has been stored in a domestic freezer for thirty years. A unique Millwall Football Club tattoo leads to the victim being identified as Matthew Walsh, a young man in his mid-twenties who went missing in March 1990.
  • List of Episodes (6)
    • 1. Episode 1

      22 Feb '21
      A dismembered body is found in a scrapyard and the team believes the remains had been stored in a domestic freezer for 30 years. Meanwhile, after making the decision to retire from the police force, Cassie faces a dilemma when she learns she isn't entitled to her full pension payment unless she completes her 30 years of service.
    • 2. Episode 2

      01 Mar '21
      Cassie and Sunny identify four potential suspects who trained as police probationers together, and two of them are still serving officers. They have no luck finding the rest of the body and decide to go public about the discovery of Walsh's remains.
    • 3. Episode 3

      09 Mar '21
    • 4. Episode 4

      15 Mar '21
    • 5. Episode 5

      22 Mar '21
    • 6. Episode 6

      29 Mar '21