“You don’t know anything about the father?”

“Nothing.”

“Was Ben especially friendly with Mary Stennet?”

“I don’t understand,” Drysdale said. “You can’t think that Ben had anything to do with the child’s death.”

“I don’t know.” George was too impatient to hide his exasperation. “Please. Just accept that I need the information.”

“Mary was the oldest child in the school. Occasionally she overwhelmed the little ones. She latched on to Ben. The others had been smothered by her for too long and were glad that she’d found another victim. He seemed not to mind her attentions but they certainly weren’t friends. There was a great difference in their ages but he was the more grown up. He tolerated her but he wasn’t dependent on her.”

“Her death doesn’t seem to have upset him?”

“No.”

That was it. He could persist with his precious theory no longer. If Mary had not learnt of Elspeth’s secret from Will or Ben, then she could not have known about it. At the back of his mind there was another idea, an explanation for Mary’s death and Robert’s, an explanation which fitted all the facts, but before he could explore it properly Sylvia came in. She was dressed in jeans and a heavy jersey, but she was wearing a lot of make-up. The moody preoccupation had gone and she seemed possessed by a disturbing and feverish gaiety. What fun it would be, she said, to catch the swans. How beautiful they would be in the torchlight. She longed to stroke them. She ran her finger along her husband’s forehead, pushing the hair away from his eyes. He was her swan, she said.

George found the scene shocking and embarrassing.

“Why don’t we put it off for another night?” he demanded. “Why is everyone so desperate to catch the swans?”

“It’s a lovely night,” Sylvia said. “ Look outside. It’s a lovely night.”

“It’s raining,” George said.

But it made no difference. They were determined to ring the swans. It seemed to George that the evening proceeded with an awful inevitability, and at such a pace that he had no time to reconsider the facts surrounding his investigation, no time to think clearly at all.

They ate a hurried meal surrounded by the debris needed to ring the swans. Both Jonathan and Sylvia talked continuously, though there was little communication. Jonathan talked about his plans for the evening. Sylvia relived her stay on Baltasay, described the things she had bought, the places she had visited. Despite the flying words he found that his new idea was growing stronger. He longed for quiet, a time to himself. He regretted the time wasted in his rush around the island from the post office to Sandwick, the wasted words.

“I don’t think I’ll come,” he said, suddenly. “I don’t feel very well. I’ll stay here.”