A new sergeant joins Scott & Bailey

Janet Scott is at home with her daughters and mother when the doorbell rings late one night. Answering the door, she sees Helen is on her doorstep. She wants to tell Janet more about what she knows concerning her parents, and the house she left over 30 years ago.

Confiding in Janet, Helen reveals that she believes her brother Michael is buried in the cellar of the house. She explains that when she was 13, her father Joe forced her to help bury her sibling. Janet is shocked at the news, and immediately tells Gill Murray of the developments.

Sending in specialist teams, Gill discovers the bodies of two adult males. Through DNA, it's clear that one is Michael. However, the identity of the second is unknown. As the police keep searching in the cellar, the bodies keep mounting until a total of seven adult males are accounted for.

It proves to be a baptism of fire for new sergeant Rob Warrington, who joins the force to tackle such a high profile and complex case.

Meanwhile, the police arrive at Strangeways prison - where Joe is serving time for the murder of his wife - to arrest him on suspicion of a double murder. Rachel interviews him back at the station, and he expresses shock when she informs him that his son Michael was found underneath his house. He lays the blame with Helen, while she's adamant that Joe is her brother's murderer.

Plus, in a bid to escape her life with Sean, it transpires that unknown to anyone, Rachel has taken to sleeping on the floor of the police office.