Season 3: Unforgotten -

(Nicola Walker): The empathetic but increasingly weary lead detective.

When the body of 16-year-old Hayley Reid is found under the M1 motorway, Cassie and Sunny reopen a case from the turn of the millennium. Hayley had gone missing while on holiday in a seaside town in 1999, and the investigation soon centers on four close friends who were staying at a nearby holiday rental at the time. Unforgotten - Season 3

: The investigation ultimately reveals that Tim Finch , the mild-mannered doctor, was responsible for Hayley's death. (Nicola Walker): The empathetic but increasingly weary lead

(Kevin McNally): A successful TV presenter with a troubled son. the mild-mannered doctor