At this, Sidney moved, and when Brooke tried to stop her she cried out, 'No! It's a woman,' and ran towards the alley's end.

She heard Justin's sharp oath behind her. He overtook her less than three yards away from the couple on the ground. 'Keep back. Let me see to it,' he said roughly.

Brooke grabbed the man by his shoulders, digging into the leather jacket he wore. The action of pulling him upwards freed his victim's arms, and she instinctively brought them up to protect her face. Brooke flung the man backwards.

'You idiots! Do you want the police after you?'

Sidney pushed past him. 'Peter!' she cried. 'Justin, it's Peter Lynley!'

Brooke looked from the young man to the woman who lay on her side, her dress dishevelled and her stockings in tatters. He squatted and grabbed her face as if to examine the extent of her injuries.

'My God,' he muttered. Releasing her, he stood, shook his head, and gave a short bark of laughter.

Below him, the woman drew herself to her knees. She reached for her handbag, retching momentarily.

Then – most oddly – she began to laugh as well.

Part Two. LONDON AFTERNOONS

1

Lady Helen Clyde was surrounded by the trappings of death. Crime-scene exhibits lay upon tables; photographs of corpses hung on the walls; grisly specimens sat in glass-fronted cupboards, among them one particularly gruesome memento consisting of a tuft of hair with the victim's scalp still attached. Yet despite the macabre nature of the environment Lady Helen's thoughts kept drifting to food.

As a form of distraction, she consulted the copy of a police report that lay on the work-table before her. 'It all matches up, Simon.' She switched off her microscope. 'B negative, AB positive, O positive. Won't the Met be happy about that?'