Gone

Impassive headmaster Michael Polly surveys a school rugby pitch as the First XV of St Bartholomew's, his team, snatches victory from the jaws of defeat - he arrives home afterwards with daughter Alana to find no sign of his wife Sarah, a music teacher at the school.

Annie is struck by Michael's strangeness in the wake of an awful discovery - a stricken Alana seeks comfort from her dad, but he is in denial as the case escalates. Meanwhile, Annie is reminded that her duties are restricted to the role of family liaison - but gets the bit between her teeth when Becky makes a technical breakthrough - as Michael is frustrated by Annie and Becky's constant presence in the house.

Michael expresses his discontent with the investigation under heated questioning, and Annie alights on Stephen Sedgwick, a new suspect who has a surprising connection to the school - Stephen insists that Sarah was unhappy in her marriage, but Annie puts him on the back foot. Over at the school, officers conduct a thorough search of the headmaster's house as Annie's boss Ivan reaches an impasse with Michael, whose alibi seems tight.

Annie and her colleagues begin to see things in a new light as fresh information continues to emerge - two suspects come to hang in the balance as each must account for their movements on the days surrounding Sarah's disappearance, and insights into their character paint a muddy picture. Meanwhile, Annie begins to let her guard down with Craig as he offers help on her cold case.

Michael is increasingly isolated as the investigation broadens and Annie doggedly pursues a new line of inquiry leading to the emergence of a compelling new suspect - sidelined in the investigation.

The final part of the chilling mystery drama. Alana, Annie and the rest of the police are reeling as Michael, who is numb with shock, is left to reckon with the enormity of what has happened.