The Ink Black Heart

When Edie Ledwell, the cocreator of the popular cartoon The Ink Black Heart, is found murdered only a few days after begging private detective Robin Ellacott for help in tracking down a mysterious online figure known only as Anomie who was persecuting her, Robin and Cormoran Strike are drawn into the quest to uncover the true identity of Anomie, a case that threatens them in horrifying ways.