Remembrance (1) (S20E05)

The discovery of a woman's body in the Thames prompts Nikki and Jack to investigate a community along the River Lee. The locals are still troubled by the disappearance of a teenager named Ruth Tresize, who went missing three years earlier, leaving behind a cloud of suspicion and sorrow. As a new series of murders strikes the area, the past resurfaces, deepening the townspeople's anguish.