DI Will Wagstaffe and his team investigate attacks on accused pedophiles; haunted by the death of his parents, Wagstaffe pushes the boundaries in the search for a killer.

Wagstaffe is frustrated by the eerie wall of silence from the victims' families; a web of deceit begins to unravel, leading Wagstaffe to a disturbing conclusion and forcing him to question the integrity of his every decision.

As the team delves deeper into the mysterious poisonings, attempts to cover up the supply chain indicate to Wagstaffe that those responsible have a powerful influence.

A young woman is found murdered in an East London church, and Wagstaffe and his team must determine whether it's the work of her recent stalker or if the answer lies in her complicated personal life.

Wagstaffe is at a crossroads when a prime suspect in the Suzy Moyland murder case is discovered dead in the same East London church; as the team delves deeper, details of her torrid emotional state reveal a surprising new line of investigation.