The explanation came to her as she was walking back from the library van. The spiteful exchange between Joanna and Marie Liddle had puzzled her. What could the women have in common? At first she had thought it might have something to do with Vic Liddle’s work. Had he been moonlighting, perhaps, for one of Simon Barton’s clients? Then she began to go over all the information she had gained since their arrival at Back Rigg, trying to tie it in with the memories she had of Joanna as a girl. She thought of Joanna’s friendship with Kate Craven. Then she remembered Alex, taking her grandchild into her arms at Monk’s Wood, waving her daughter away to work. She remembered a letter received from Ursula many years before in which she was informed of Joanna’s mysterious illness and the fact that the Liddles had decided to adopt a brain-damaged child. That both events had happened at the same time now took on a special significance. Quite suddenly all the facts fell into place and she was astonished by her stupidity.

At the farm she began, absentmindedly, to tidy Ursula’s garden. As she pushed the mower over the straggling grass and pulled weeds from the overgrown borders, she made her plans. George would not be back from London until almost midnight. That gave her the evening to make sure of her facts before presenting the case to him. She was determined that he would not ignore her again. After an hour she decided that she was making no impression on the chaos of the garden and went into the house to wash and change into something more respectable. After a brief search of the obvious places she found the keys to Ursula’s Land Rover in the kitchen on a hook next to the sink. At three o’clock she began to drive jerkily down the track towards Appleworth.

She found the special school without any problems, directed to it by a traffic warden from the town centre. It was a pleasant, modern building right at the edge of the town, beyond a small council housing estate. There were views of the fells and no shelter from the westerly wind. In the winter the children would have to be tough to play outside. The place seemed deserted. The children had all gone – either to their homes or to the hostel where the more severely handicapped were cared for. But it was not yet four o’clock and Molly thought that the teachers must still be inside. She parked the Land Rover opposite the main gate and waited, patiently, almost dozing.