Struggling to adapt to the loneliness of his retirement, Len finds himself drawn back to his on-going investigation into Melissa's unexplained death. With time on her hands as she waits for the baby's arrival, a concerned Vidya helps Len and they discover the house is reluctant to give up its secrets. As he questions the residents, Len slowly pieces together how they knew Melissa. Is the beautiful but controlling Elaine telling him the whole truth? And what might she do to stop her girlfriend Peggy from leaving her?

The four-part drama comes to a shocking conclusion.

With the residents of Coulthard Street moving on and the inquest into Melissa's death now complete, Len finds it hard to let go. When a suspect makes a shocking confession Len doubts the outcome and goes to extreme lengths to solve the case before it is too late. When he stumbles across the hidden past of one of the residents he must appeal to his former colleagues to help make an arrest.

Are the residents of Coulthard Street still in danger? More importantly - who really murdered Melissa Young?