1911: Inside an asylum at the edge of the Yorkshire moors, where men and women are kept apart by high walls and barred windows, there is a ballroom vast and beautiful. For one bright evening every week they come together and dance. When John and Ella meet it is a dance that will change two lives forever. A page-turning tale of dangerous obsession, of madness and sanity, and of who gets to decide which is which. A poignant against-the-odds love story.