It's two o'clock in the morning when Andrew Gulliver gets a phone call from his mother. His twin sister, Annie, is gone. Nothing unusual in that - she's been taking off since she was a child. But this time is different. Last month, she got into serious trouble in Sicily, was attacked and ended up in a mental hospital, diagnosed as a schizophrenic...But until now, her family and her twin have refused to accept that something is really wrong. She must be found before she harms herself or someone else...