Somewhere in the crowd is a killer. Bonfire Night and St James's Park is filled with thousands of Anonymous protesters in a stand-off with the police. When a body is discovered, DCI Kate Riley and DS Zain Harris are called in to investigate. The corpse has been eaten away by a potentially lethal and highly contagious virus. And time is running out. Kate and Zain identify the victim as a senior civil servant, whose work in international development involved saving lives. Why, then, would anyone want him dead? With lives at stake, Kate and Zain race against the clock to uncover the truth behind the attack, before the killer strikes again.