When Eliza's father dies, he leaves her penniless in a time where marriage is her only option for financial security. But the headstrong Eliza is determined to find another way. Luckily, she has an ace up her bonnet – her father's business – a private detective agency. Eliza knows all the tricks of the trade but as a genteel 19th century lady she's never been allowed to put them into practice. To operate in this man's world, she needs a partner. Step forward Detective Inspector William Wellington of Scotland Yard, who is also known as "The Duke;" drinker, gambler and womaniser. Eliza and The Duke strike up a mismatched, fiery relationship that will crackle and smoulder with sexual tension as they team up to solve crime in the murkiest depths of 1880's London.