“Before I leave the island,” she said, “ I check that the bedrooms are tidy. Elizabeth is a good worker. I do not believe that she is adequately paid for what she does, nor sufficiently appreciated by the residents. We should not presume on her good nature, especially now that she is expecting a child. So I go into every bedroom, once the guests have finished, and fold the blankets neatly, empty the waste-paper basket. I repeated this procedure on Sunday. I saw no reason to behave differently because of the outrages which have occurred. In the doctor’s bedroom I found these scraps of paper in the waste bin.”

The paper was a letter or, George thought, the draft of a letter, because certain parts had been rewritten, words had been crossed out.

“My dearest Sian,” it began. “ You will never receive this letter. None of the letters I write will ever reach you. I know better than to hurt you like that, especially now. You must not miss your mother too much. When you are older you will realize that she was not worthy of you. But I am writing, my dear, to tell you that we are safe. Charlie Todd is dead, and I have retrieved from him that which he would have used against us. So remember, my dear, that I will always be your fond friend, Paul.”

“I knew of course about his affection for young girls,” Jasmine Carson said. “I have seen it before. I worked with children for forty years. Before he went into general practice he worked in the hospital in Gillicombe. He made a fool of himself with some of the younger nurses, but they were able to look after themselves. Sian Marshall is only a child. I had not realized, I admit, how deeply he cared for her.”

“Sian is Pamela Marshall’s daughter?”

“Yes. Her youngest child.”

“How old is she?”

“Thirteen, fourteen perhaps, but rather immature for her age. Pamela always said that she worried about the girl, but I saw no evidence of her concern. She was always happy enough to leave her alone to go off on her conferences and committee meetings.”

“What made you look at the pieces when you were emptying the basket?”

“One of the larger pieces included the words ‘Todd is dead’. I was curious and put the pieces in my pocket. It’s a habit. From my schoolmistress days, I suppose, when it was my duty to take an unnatural interest in my charges’ behaviour. When I got home and saw Sian’s name on the paper I felt no guilt in piecing the thing together.”

“Why didn’t he burn it? It would have been safer.”

“The only fire was in the common room. He may have been reluctant to take it there.”

“Do you think that the doctor had actually made any advances towards Sian? Did Pamela know about his infatuation?”

“I’m sure that she did not. She was supposed to leave her children with anyone who would look after them. Sian went occasionally to spend an afternoon with Paul Derbyshire and his wife. I doubt whether he has done or said anything at all improper. He’s a weak and foolish man, and that nonsense …” she pointed at the letter “… is nothing but fantasy.”