Members of the public are being poisoned at random, and as McCallum investigates their deaths, he comes to the realization that he might be the real target.

A Brazilian prostitute dies from what turns out to be a "superbug" bacterial infection, setting McCallum on the trail of an illegal-immigrant scam. Can McCallum track down the source of the lethal bacteria before it spreads through London?

When East End baker Alan Konrad dies, it looks like an accident at first. Konrad had a successful business, a happy marriage, and a prosperous family. But as McCallum gets closer to the truth, he opens a Pandora's box of lies and deceit.