“Do the police still think that the murderer was one of us?” Jasmine Carson faced the communal fear with characteristic directness.

“I’m sorry. I don’t know anything. Savage came to see me today. He said that I was to be released, unconditionally, and asked if I would like to spend the day on the island. He said that George had arranged something special.”

Paul Derbyshire gave a peculiar moan. “No,” he said. “I can’t stand it. It’s all going to start again. All the prying into our private lives. All the worry and unpleasantness. It’s too much.”

“I think,” Jasmine said, crisply and disapprovingly, “that Nicholas has suffered more unpleasantness than we have, and that it would be rather churlish not to celebrate his release.”

The doctor seemed not to hear.

“I took the liberty,” George said, carefully changing the subject, “as the only committee member on the island, to ask John to prepare his equipment for cannon netting. I must confess that I’m fascinated to see it work, and the conditions today are superb. There have been massive roosts of redshank and oystercatcher all week. I take it that no one has any objection?”

He looked directly at Jasmine Carson. She admitted defeat easily, smiled and shook her head.

Molly had been as surprised as anyone by the appearance of Nicholas Mardle. It was hard now, as he stood by the hearth, the centre of attention, to believe in George’s image of him as a disturbed and miserable adolescent. Could four days in a police cell have changed someone so dramatically? She found it hard to accept. She supposed that she must trust George.

As if in deference to Nicholas’s good fortune, they did not mention the murders or the police again. They began to plan the operation of cannon netting. John took charge.

“George and I set the net earlier this morning,” he said. “You have to prepare it a long time before high water, so that the birds aren’t disturbed. We’ll fire the cannon when the birds are roosting, just after high tide. I’ll want everyone to keep well out of the way then. It can be dangerous.”

“I hope that there will be no harm to the birds.” Jasmine had accepted that the operation would take place, but could not refrain from voicing her objections.

“There shouldn’t be.”

“How exactly does the thing work?”

“The birds have been roosting on that flat, grassy area to the south of the Wendy House. That’s ideal for our purposes, because the halfway wall can act as cover. There’s a plunger, well behind the wall, which fires a series of projectiles to which the net is attached. The explosion, sends the big net over the birds. Then we’ll have to be really well organized to ring and process the waders as quickly as we can. I must stress how important it is to stay behind the cannons when we’re ready to fire. And do keep away from the equipment now, because it’s all set. I’d hate there to be an accident. Especially today. Now, is anyone interested in going round the traps before lunch?”