It was five o’clock, and in the long shadow it was pleasantly cool after the heat of the day. Somewhere in the village there was a bonfire.

“Did he ever talk to you about Greg Franks?” George asked.

She shook her head. “Is that the boy who died?”

“Yes.”

“No,” she said. “ I’ve never heard of him.”

“He’s a birdwatcher,” George said. “A twitcher. He’s quite famous in his own circles. The police believe he was bringing drugs into the country.”

“Duncan would never be involved in anything like that.”

“No,” George said. “I don’t believe he would. Unfortunately there is a connection between Duncan and Franks. About a year ago a letter arrived at Greg’s parents’ house. He was still officially living at home then, though he would disappear for days, even weeks, at a time. The letter arrived during one of his frequent absences, and his mother opened it. It was a large cheque, and it was sent from this address. You say you’ve never heard of Greg, so presumably you didn’t send it. That leaves Duncan.”

She shook her head. “ There must be some mistake,” she said. “I don’t know anything about it.”

“You do see how it looks,” George persisted. “Franks was a known drug dealer. Duncan paid him a large sum of money. That implicates Duncan in the drugs, don’t you see?”

“I can see how it looks,” she said, “ but it’s impossible.”

“You can think of no other reason Duncan might have had for paying Franks?”

“No,” she said. “ None at all.”

He found it impossible to follow the line of questioning, and there was a pause in the conversation. In the tall trees behind the house he heard wood pigeons calling, and in the garden behind the wall there was the sound of a hose.

“Why did Duncan go to Cornwall this weekend?” George asked at last.

“He was tired,” Anne said. “He needed the break.”

“I shouldn’t have thought it was his sort of thing at all. When did he decide to go?”

“Last weekend,” she said. “ It was all rather sudden. I was pleased; I thought he could do with a holiday. There’s a lot of pressure on the sites of scientific interest in the area, and he’s been under strain for months.”

“How did he come to hear of the trip?”

“I don’t know exactly,” she said. “I presume it was some sort of circular. A letter came for him on Saturday morning, and later that day at dinner he said something like ‘This looks interesting. Would you mind if I went?’”

“Did you read the circular?”

“No,” she said. “But if you want to see it, I expect it’s still in Duncan’s office. He never throws anything away.”