As Chandler and Miles attend the christening of Miles's daughter, a fox runs through the streets of Whitechapel with a human arm in its mouth. Soon, more body parts from the same victim are washed up by the river, all containing evidence of a fatal poisoning. Buchan believes the crimes echo the Thames torso murders of the 1880s - can the team, with the help of a female DI attractively like Chandler in her habits, crack the gruesome case?