Frannie stands trial. The shocking truths about the Benhams' murders, Langton's experiments and Frannie's past are revealed.

Frannie and Madame's relationship comes under threat as jealousies flare in the Benham house, and Madame's own issues worsen.

Frannie and Madame's illicit relationship develops. Meanwhile, we learn about the horrific experiments conducted at the Paradise plantation.

London, 1826: When prominent society couple Mr. and Mrs Benham are found stabbed to death, their maid Frannie Langton is accused of murder.