The Gaudy Shadows — John Brunner

Tileman could make our fantasies come true - create reality from your dreams - for a very high fee. Catering to the desires of London's most powerful - and decadent - figures, Tileman had top-level connections to guarantee him protection and influence.

But he had killed Laird Walker's best friend - and Walker, the dead man's sister, and a bizarre nightclub entertainer began a private war on Tileman...a war whose final battle was unimaginable horror.