The Magpie has murdered a wealthy businessman in his own home, sparking fear among London's population that no one is safe from this supernatural threat. Pressure mounts on a police force with no leads, but disgraced private detective Ignatious Thorn makes a startling discovery about his own connection to the killer.

Elsewhere, medium Madame Hendrikov claims she has information from the spirit world about the Magpie. Barmaid Bess Turner moves deeper into the capital's criminal underworld, and faces a deadly test of loyalty when someone she cares about is in the wrong place at the wrong time. And all the while, the Magpie gets closer and closer to the mastermind who sits at the center of everything, like a spider in its web.

But if he's the spider, does that make the Magpie his prey?