The next day, Wednesday, his helplessness turned to aggression. From his weakness and his lack of power, which was illustrated by Stella’s ability to use him, grew a violent anger that acted like a drug. It stopped him from thinking clearly and prevented him from considering the options that had seemed to provide a way out earlier in the week. He wanted revenge for the sleepless nights of worry, the disruption to his family life, even for his own sense of guilt. Someone had to pay.

The first person to pay had been Judy. At her insistence, he had returned home for lunch and at first it was pleasant. The kitchen door into the garden was open and the twins were playing happily outside. The children’s voices and the birdsong and the mild spring sunshine relaxed him and he thought his worry had been unnecessary. He would help Stella once more, he thought, just once more, then it would all be over. But Judy began again to question him about his conversation with Alice on the evening of her death and he lost his temper.

“It’s none of your business,” he shouted. “None of your bloody business.”

The twins stopped their game and stared through the open door, fascinated by his anger. Judy cried and there was a humiliating scene as she put her arms around him, dripping tears all over his face.

“Please, Max,” she said. “I don’t care what you’ve done. I can handle anything. But I can’t take this silence. I want you to trust me.”

Then he turned on her. “You think I killed Alice,” he shouted. “Don’t you? How can I trust you when you think me capable of that? What about Charlie Elliot? Do you think I murdered him, too?”

“I don’t know,” she cried. “I really don’t know. I want to know where you were on Tuesday morning. I got up to see to the twins and you weren’t there. What am I supposed to think?”

“I’m a doctor,” he yelled. “I get called out in the middle of the night. You should be used to that by now.”

Then he left the house, only half hearing the voice behind him calling him to come back, begging him to talk to her. He was pleased that he was hurting her.

He had one house call to do, and to his surprise he completed it calmly and efficiently. It was only as he drove to the other side of Otterbridge that the sense of imminent violence returned and grew. He drove automatically because he knew the road well, and when he arrived at the Laidlaws’ house, it was with surprise, because he could not remember how he got there. He walked across the gravel, past the pool of crocuses, purple against the green of the lawn, and thumped on the door with his fist.