Victoria's London was the queen of the universe, a dazzling metropolis from whose magnificent mansions and discreetly luxurious clubs flowed the strategies that built the greatest empire ever known. Meanwhile, the city's poor suffered and died in hopeless obscurity. Inspector William Monk knows his city's best and its worst - or so he believes, until the day when charming Genevieve Stonefield comes to plead with him to find her missing husband.

In his family life, Angus Stonefield had been gentle and loving; in business, a man of probity; and in his relationship with his twin brother, Caleb, a virtual saint. Now he is missing, and it appears more than possible that Caleb - a creature long since abandoned to depravity - has murdered him.

And so Monk puts himself into the missing man's shoes, searching in Stonefield's comfortable home, his prospering business, his favorite haunts, and, finally, the city's dangerous, fever-ridden slums for clues to Angus's fate and his vicious brother's whereabouts. Slowly, Monk inches toward the truth - and also, unwittingly, toward the destruction of his good name and livelihood...