Esther's feelings for Woodcourt grow stronger despite her best intentions. Inspector Bucket begins his murder investigation with no shortage of suspects. An early arrest appears to wrap the case up quickly, but a spate of poison pen letters suggests that all is not as it seems.

As Bucket wraps up his investigation, there's yet more trouble for Lady Dedlock in the shape of the evil moneylender Smallweed, who has evidence of her secret past and intends to use it. Cornered and desperate, Lady Dedlock makes a terrible decision.