He's watching.
A gunman is stalking the wards of a local hospital. He's unidentified and dangerous, and Police Firearms Officer Aden McCarthy is tasked with tracking him down. Still troubled by the shooting of a schoolboy, Aden is determined to make amends by finding the gunman - before it's too late.
She's waiting.
Psychologist Imogen has heard about the gunman, but he has little to do with her. Or has he? As time ticks down, no one knows who the gunman's next target will be. But he's there. Hiding in plain sight. Far closer than anyone thinks...