But George did not laugh. “Are John and Elizabeth hard up?” he asked.

“I don’t know. I get the impression that they don’t have much money. Is it important?”

“I don’t know. It might be.”

“We’re going to see Doctor Derbyshire next, aren’t we?” she asked. “ I wonder if we’ll get anything interesting out of him.”

She bit into her second ham and tomato roll.

She’s not shocked by anything, he thought. She worked with people who were in pain for so long that she detached from it. He found the doctor’s taste for young girls unpleasant, even disgusting.

“I wonder if the wife knows,” she said, and her voice did express some emotion now. “How dreadful if she does, and she still cares for him. She must be so frightened for what he might do.”

“Might he be dangerous?”

“I suppose he might. It all seems to be confined to the realms of fantasy, though. So long as it’s all a sort of glorified daydream, I should think he’d be safe.”

“Yes,” George said. “But the difference between fantasy and reality might not be so obvious to someone else.”

“What do you mean?”

“Well, suppose that Charlie found a letter, or a diary, full of the doctor’s ramblings, he couldn’t be expected to know that the events described were only make-believe. Charlie liked children too. He wrote stories for them. Besides his curiosity about other people’s personal affairs, it might have occurred to him that he should have done something about his discovery of the doctor’s predilections.”

“So he threatened to go to the police, and the doctor strangled him.”

“The letter which Jasmine found could certainly be read like that. He could have arranged to meet Charlie in the seawatching hide very early, before Jerry was due to arrive, to discuss it.”

“But how could he be sure that Jerry wouldn’t suddenly arrive and surprise him?”

“The flaps of the seawatching hide open on all sides. It’s possible to see someone as soon as they leave the observatory.”

“Do you think that’s how it happened?”

“No, but we must see him anyway.”

From the start Molly was intrigued by the tone of the conversation between Paul Derbyshire and his wife, Marjory. She was a tall woman, calm and slow-speaking, with an air of assurance. She was polite, but distant, as if her mind were elsewhere. They lived in a big house, near to the shore, at the end of a long straight road of similar houses. It was out of the town, near the golf course. There were no trees, and the wind blew up the bleak, straight street and around the ugly brick houses. The house was separated from the water by a stretch of dunes, and as George and Molly got out of the car, sand blew in sharp swirls around their ankles and stung their eyes. Sand was piled like a snowdrift outside the boundary fence.

Marjory opened the door to them. She did not speak, but stood, patient and serene, waiting for them to announce their business. She was dressed in expensive, conventional, nondescript clothes. Her hair was grey, permanently waved. George, whose temper had not improved, stated their business shortly. She invited them in and called to her husband: