Hannah's always loved a bad boy, but marrying a serial killer might be a step too far... Meet Hannah: unlucky in love, struggling at work, and increasingly lonely as her friends settle down one by one. Meet William: classically handsome, successful in his career, and behind bars for killing multiple women. It's not exactly a likely meet-cute, but after writing William a series of angry letters to vent about what he's done and everything she's going through, Hannah suddenly finds herself not only engaged to him, but living in his home. Hannah's pretty sure that this will all work out okay. But how blissfully happy can you really be if you're worried you might be your fiancé's next victim?