Aileen Seaton, a woman lawyer and former fencing champion, hears a dying man's confession. He swears the best-selling Scottish writer, Calum Weir, is innocent of the double murder of his wife and her lover.When Aileen meets Weir, in prison for life, she realises he remembers nothing of the horrific murders. But why, she asks, is he even scared to talk about them? And why do his terrifying nightmares involving the poisonous plant, monkshood?Together they reconstruct the murder scenario, and interrogating the writer's previous lovers, his friends and rivals, Aileen feels sure someone plotted to incriminate Weir and put him away for life.As she pierces the enigma the killers come after her to shut her mouth. Only her talent with an old duelling sword can save her.