Short Story: Flirting with disaster

He was 45 when his marriage ended, decisively, on a soft autumn day, the last of the barbecue weather.

 Nothing about that day was his plan, nothing his intention, though later you could see that every element of the disaster was in place. Above all, Lorraine was in place, standing by the cavernous American fridge, stroking its brushed steel doors with one lacquered fingertip.

''Do you ever get in it?" she said. ''I mean, on a really hot day?"

''It wouldn't be safe," he said. ''Doors could swing shut."

''Jodie would miss you. She'd let you out."

''Jodie wouldn't miss me." He understood it only when he said it. ''Anyway," he said. ''It's not been that hot."

''No?" she said. ''Pity."

She stretched up and kissed him on the mouth.

Her wine glass was still in her hand and he felt it roll, cool and damp, against the back of his neck, and make a creeping down his spine. He scooped her against him: a motion of ample gratitude, both hands around her bottom. She murmured something, stretched out an arm to put the glass down, then gave him her whole attention, her open mouth.

He had always known she was available. Only not found her alone, on a warm afternoon, her face a little flushed, three glasses of Vinho Verde from complete sobriety. Never alone because Lorraine was the sort of girl who moved in a crowd of girls. She was round, kind, downmarket for the neighbourhood and easy to like. She said droll things, like, ''It's so sad to be called after a quiche." She smelled delicious, and of kitchen things: plums and vanilla, chocolate.

He let her go, and as he relaxed his grip he heard her tiny heels click back on the floor. ''What a little doll you are," he said. He straightened to his full height. He was able to picture his own expression as he gazed down at her: quizzical, tender, amused; he hardly recognised himself. Her eyes were still closed. She was waiting for him to kiss her again. This time he held her more elegantly, hands on her waist, she on tiptoe, tongue flickering at tongue. Slow and easy, he thought. No rush. But then, crudely, his hand snaked around her back, as if it had a will of its own. He felt for her bra strap. But a twist, a flinch told him, not now, not here. Then where? They could hardly shove through the guests and go upstairs together.

He knew Jodie was rattling about the house. He knew - and he acknowledged this later - that she might at any moment blunder in. She did not like parties that involved open doors, and guests passing between the house and the garden. Strangers might come in, and wasps. It was too easy to stand on the threshold with a burning cigarette, chatting, neither here nor there. You could be burgled where you stood. Picking up glasses, she would push through groups of her own guests, guests who were laughing and passing mobile phones to each other, guests who were, for Christ's sake, trying to relax and enjoy the evening. People would oblige her by knocking back what was in their glass and handing it over. If not she would say, ''Excuse me, have you finished with that?" Sometimes they made little stacks of tumblers for her, helpfully, and said, ''Here you go, Jodie." They smiled at her indulgently, knowing they were helping her out with her hobby. You would see her off in her own little world, her back to everyone, loading the dishwasher. It was not unknown for her to run a cycle before the party was an hour old. The time would come, after dusk, when wives got maudlin and husbands boastful and bellicose, when spats broke out about private schooling and tree roots and parking permits; then, she said, the less glass there is about, the better. He said, you make it sound like some pub brawl on an estate. He said, for God's sake, woman, put down that wasp spray.

All this he thought, while he was nibbling Lorraine. She nuzzled him and undid his shirt buttons and slid her hand over his warm chest, and let her fingers pause over his heart. If Jodie did come in, he was just going to ask her quietly not to make a scene, to take a deep breath and be more French about it. Then when the people had gone home he would spell it out: it was time she slackened the rein. He was a man at his peak and must see some pay-off. He alone by his professional efforts kept them in hand-built kitchens. He was pulling in an amount seriously in excess of anything she could have expected, and his shrewdness had made them near as dammit recession-proof; who could say the same, on their patch? And after all, he was prepared to be fair. ''It's not a one-way street," he would say to her. She was a free agent, as he was. She might want an adventure of her own. If she could get one.

He dropped his head to whisper in Lorraine's ear. ''When are we going to f*&k?"

She said, ''How about a week on Tuesday?"

It was then his wife arrived, and paused in the doorway. Her bare arms were drooping stems, and glasses like fruit hung from her finger ends. Lorraine was breathing hotly against his chest, but she must have felt him tense. She tried to pull away, muttering: ''Oh bugger, it's Jodie, jump in the fridge." He did not want to part from her; he held her elbows, and for a moment stood and glared at his wife over Lorraine's fluffy head.

Jodie moved a pace or two into the kitchen. But she stopped, her eyes on them, and seemed to freeze. A tiny chime hung in the air, as the glasses shivered in her fingers. She did not speak. Her mouth worked as if she might speak, but only a squeak came out.

Then her hands opened. The floor was limestone and the glass exploded. The crash, the other woman's cry, the splintering light at her feet: these seemed to shock Jodie into reaction. She gave a little grunt, then a gasp, and put her right hand, now empty, on to the slate worktop; then she folded to her knees. ''Watch out!" he said.

She sunk into the shards as smoothly as if they were satin, as if they were snow, and the limestone gleamed around her, an ice field, each tile with its swollen pillowed edge, each with a shadow pattern faint as breath. She snorted. She seemed dazed, concussed, as if she had smashed a mirror by putting her head through it. She reached out her left hand, and her hand was cut, and a springing well of blood branched into tributaries on her palm. She glanced at it, almost casually, and made a gagging noise. She folded tidily back on to her heels. She fell sideways, her mouth open.

He trod on the glass to get to her, crunching it like ice. He thought this was his chance to slap her, that she was faking to scare him, but when he dragged at her arm it was limp, heavy, and when he shouted Christ Almighty Jodie she didn't flinch, and when he jerked her head round brutally to look into her face, her eyes had already glazed.

So it seemed to him later, when the night's events had to be reprised. He wanted to cry on the shoulder of the ambulance crew and say, only curiosity and mild lust led me on, and a sort of childish defiance, and the fact that it was there for me, on a plate, do you know what I mean? He said, I meant to ask her to be French. Probably she wouldn't have been, but I didn't think she'd fall over like that ... I mean, how would you? How would you imagine that? And kneeling, kneeling on the glass.

For the first day or so he was not coherent. But nobody was interested in his state of mind; not in the way they would have been, if he had been in custody for killing his wife in some more obvious way. A doctor explained it to him, when they thought he was ready. Long QT syndrome. A disorder of the heart's electrical activity, which leads to arrhythmia, which leads, in certain circumstances, to cardiac arrest. Genetic, probably. Underdiagnosed, in the population at large. If we spot it early, we doctors can do all sorts of stuff: pacemakers, beta blockers. But there's not much anyone can do, if the first symptom is sudden death. A shock will do it, he said, or strong emotion, strong emotion of any sort. It can be horror. Or disgust. But, then again, it doesn't have to be. Sometimes, he said, people die laughing.

• This is an extract from Mantel's collection of short stories 'The Assassination of Margaret Thatcher'. Published by Harper Collins (R290), the book will be in stores at the end of the week