‘I . . . I was just walking, that’s all. I often walk, you know that.’

Elaine still sat staring at him, her eyes hard and steely. She ran her tongue over her lips before she spoke. George’s eyes were glued to her, watching every nuance.

‘In all the years we’ve been married, George Markham, I can count on one hand the times you went out walking alone. Now all of a sudden you’re never in the house. I want to know where you go. And I’m warning you, George, you lie to me and there will be murder done in this house tonight.’

He stared at her for a few seconds and then he felt it: the high-pitched giggle that came from his stomach and gradually worked its way up to his throat. He tried valiantly to calm himself, swallowing heavily, but to no avail.

He burst into nervous, high-pitched laughter. Like a child who laughs out of sheer terror when being told off by his teacher. In his mind was one word: murder.

He had already committed one murder tonight. Elaine would murder the murderer. Every time he thought of it it sent him into gales of hysterical laughter. Where had the time gone? Where the hell had the time gone?

‘George?’ Elaine was standing now. His laughter was frightening her. ‘For Christ’s sake, George, calm down.’

He had dropped on to his knees, his hand holding his stomach. Tears were rolling down his face.

He was heaving with mirth. A strange sinister mirth. Elaine stood and watched him until he was quiet.

When George was finally capable of movement, he pulled his handkerchief from his pocket and blew his nose vigorously before he pulled himself on to the nearest chair. The laughter was all gone now, only fear of discovery remained. His knife-sharp brain was ticking away as he watched his wife. Did Elaine guess?

‘There’s something not right, George, I know it. All this walking, being gone for hours - is not like you. I have to drag you from the house normally even to go shopping.’ She sat down heavily in the other chair.

‘I want to know exactly what’s going on.’ Her voice brooked no argument, but deep inside she did not want to know. She did not want to believe what the rational part of her was dreading.

George sat quietly, twisting the handkerchief between his fingers. He needed something that would throw Elaine off the scent completely. Then it jumped into his mind and he grabbed at it like a drowning man a straw. He looked at her, gathering every ounce of sorrowfulness he could muster into his lacklustre grey eyes.

‘I have a terrible problem, Elaine. I’ve been going out of my mind with worry about how to tell you. Something dreadful has happened.’