When frantic, dishevelled Edie Ledwell appears in the office begging to speak to her, private detective Robin Ellacott doesn't know quite what to make of the situation. The co-creator of a popular cartoon, The Ink Black Heart, Edie is being persecuted by a mysterious online figure who goes by the pseudonym of Anomie. Edie is desperate to uncover Anomie's true identity. Robin decides that the agency can't help with this - and thinks nothing more of it until a few days later, when she reads the shocking news that Edie has been tasered and then murdered in Highgate Cemetery, the location of The Ink Black Heart. Robin and her business partner Cormoran Strike become drawn into the quest to uncover Anomie's true identity. But with a complex web of online aliases, business interests and family conflicts to navigate, Strike and Robin find themselves embroiled in a case that stretches them to their limit.

Edie Ledwell, the co-creator of a cult TV cartoon, The Ink Black Heart, is being harassed by an online figure, Anomie. She asks Robin to uncover Anomie's true identity.

Robin, Strike and Barclay all take risks to further the investigation now that they think Anomie probably killed Edie Ledwell. Strike receives an unexpected and unwelcome visitor.

Robin and Strike make a major breakthrough, having eliminated several suspects. Robin's cover is blown, and Strike stays the night at her new flat. Meanwhile, Anomie claims another two victims.

The agency is the target of a devastating attack. Strike figures out who killed Edie, and having secured proof, Robin puts herself in danger in order to save lives.