When two social workers, investigating reports of child abuse, appear at Brenda Scupham's door, her fear of aurthority leads her to comply meekly with their requests. Even when they say that they must take her seven-year-old daughter Gemma away for tests...

It is only when they fail to return Gemma the following day that Brenda realizes something has gone terribly wrong.

At the same time, Banks is investigating a particularly unpleasant murder at the site of an abandoned mine. Gradually, the leads in the two cases converge, guiding Banks to one of the most truly terrifying criminals he will ever meet...