Nancy Means Wright has situated her book in Mitchelstown Castle in County Cork Ireland, 1786, where the infamous Anglo-Irish Kingsborough family resides. Mary Wollstonecraft has been hired as a governess for some of the numerous children. On her voyage from England to Dublin Mary meet a sailor, Sean Toomey who gives her a letter to deliver to a 'Liam'. Within minutes she watches Sean go overboard with a knife in him. After a few days at the castle there is a so-called pagan bonfire and the illegitimate son of the Lord is murdered. Later the Irishman Liam Donovan is considered the prime suspect in the murder. Mary is determined Liam is innocent and is resolved to find the real murderer. She thinks the two murders are connected. Secrets and intrigue follow.
'Midnight Fires' is positioned at a time when the Catholics and Protestants were fighting for independence from England as well as battling against each other. Poverty is the life of the Irish working class and Wright presents a penetrating look at the difference in the social classes. She does this with memorable characters, their experiences and everyday reality in that time period. Nancy Means Wright gives us great insight into the history, both social and political, with great ease.