Hetty plans to rescue a kidnapped girl, leading to a final confrontation with her old enemy.

Hetty discovers an explosive secret, while Gideon fears he caused Edwin's life-threatening accident. Fierce Lady Grenford arrives to help Rosamund with the birth of her new baby.

Hetty is forced to cover when Rosamund goes missing on the day of the christening, while Gideon and Jack find themselves in muddy trouble. Mrs Brody takes control of the house.