Leeds, England. October, 1897. Superintendent Harper is proud of his wife Annabelle. She's one of seven women selected to stand for election as a Poor Law Guardian. But even as the campaign begins, Annabelle and the other female candidates start to receive anonymous letters from someone who believes a woman's place lies firmly in the home.

The threats escalate into outright violence when an explosion rips through the church hall where Annabelle is due to hold a meeting - with fatal consequences. The only piece of evidence Harper has is a scrap of paper left at the scene containing a fragment from an old folk song. But what is its significance?

As polling day approaches and the attacks increase in menace and intensity, Harper knows he's in a race against time to uncover the culprit before more deaths follow. With the lives of his wife and daughter at risk, the political becomes cruelly personal .