A tense, chilling story of a nightmare come true . . .

A brutal serial killer stalks the Seattle nights. Regina Greenleaf was one of the victims. Her beautiful twin sister, Renata, is deeply traumatised.

Renata barely knows she's alive. She talks only rarely, and then always in twin-speak, the special language she and Regina made up long before they'd learned to speak English.

When there had been two of them, they used to swap names. At school, they'd swapped the ribbons in their hair which were the only way of telling them apart. They were so close to each other, they might as well have been one person.

Mark, a college lecturer in English, is Renata's friend and her post-trauma protector. He's the only person Renata recognises and will talk to. She agrees to attend his classes, and with the help of Mark's room-mates Renata seems to be coming to terms with her loss.

But the number of murders in Seattle rises, and Mark has some dreadful suspicions. If he says anything, it's guaranteed to send Renata back to the hospital. But if he doesn't, there may be blood on his conscience . . .