There was a noise from the field next to the track. Not gunshot this time but a muttering, ripping and stamping of feet. Sandy turned, saw the silhouette of the cow just a few feet away. Mima was the only person left on Whalsay who milked by hand. The rest had stopped decades ago, put off by the work, and the hygiene regulations, which prevented the milk being sold. There were people though who still liked the unpasteurized milk and fixed Mima’s roof or slipped her a bottle of whisky in return for a jug of the yellow liquid every morning. Sandy wasn’t sure they’d be so keen if they saw Mima milking. Last time he’d seen her do it, she’d blown her nose on the filthy tea-towel she went on to wipe the udders with. As far as he knew, though, no one had gone down sick as a result. He’d been brought up on the stuff and it had done him no harm. Even his mother scooped the cream off the top of the churn and put it on her porridge for a treat.

He pushed open the door into the kitchen, expecting to see Mima in her chair by the Rayburn, the cat on her knee, an empty glass by her side, watching something violent on the television. She was never one for going to bed early, hardly seemed to sleep much at all, and she loved violence. She was the only one of his family who’d been pleased by his choice of career. ‘Fancy,’ she said, ‘a cop!’ She’d had a kind of dreamy look in her eyes and he’d been sure she’d been imagining New York, guns, car chases. She’d only been south once, to Aberdeen for a funeral. Her pictures of the world came from the TV. Policing in Shetland had never been much like that, but she still enjoyed hearing his stories, he exaggerated them, just a touch, to make her happy.

The television was on, the sound horribly loud. Mima was going deaf, though she refused to admit it to the family. But the cat lay on its own in the chair. It was large and black and vicious to everyone but its owner. A witch’s cat, his mother called it. Sandy turned down the sound, opened the door to the rest of the house and shouted. ‘Mima! It’s me!’ He knew she wasn’t asleep. She’d never leave the light and the telly on, and the cat shared her bed as well as her chair. Mima’s husband had died in an accident at sea when she was still a young woman. There were rumours of her being a wild young widow, but since he’d known her she’d lived on her own.

There was no answer. He felt suddenly very sober and walked through to the rest of the house. There was a corridor which ran along the back of the three rooms and led into each one. He couldn’t remember ever going into her bedroom before. She’d never been ill. It was a square room taken up with a heavy dark-wood wardrobe and a bed so high that he couldn’t see how Mima could scramble on to it without a step. There was the same thick brown lino on the floor as in the kitchen, a sheepskin rug, white once, now grey and rather matted. The curtains, faded and tatty, cream with a design of small roses, weren’t drawn. On the windowsill stood a photo of her husband. He had a thick red beard, very blue eyes, was dressed in an oilskin and boots and reminded Sandy of his father. The bed had been made and covered with a quilt of crocheted squares. There was no sign of Mima.

The bathroom was a more recent addition, built on to the back of the house, though it had been there as long as Sandy could remember. The bath and the basin were an improbable blue, though there was still brown lino on the floor, partly covered by a bright blue shaggy rug. A smell of damp and wet towels. An enormous spider crawled around the plughole. Otherwise the room was empty.

Sandy tried to think rationally. He’d dealt with missing-person inquiries and knew that families always panicked unnecessarily. He’d made fun of the anxious parent or partner once he’d put down the phone. ‘There was a party at the Haa last night. That’s where they’ll be.’ But now he felt the shock of the unexpected, the unknown. Mima never strayed from her house at night these days, unless there was a family do at his parents’ house or a big island event like a wedding, and then someone would have given her a lift and he’d know about it. She had no real friends. Most Whalsay folk were slightly afraid of her. He felt his thoughts spinning out of control, tried to keep calm. What would Jimmy Perez do in this situation?

Mima always shut her hens up at night. Maybe she’d gone out to do that and tripped and fallen. The archaeologists had dug their trenches on some land right away from the house, but she was getting on now and it was possible that the drink was at last clouding her judgement. If she’d wandered down that way it would be easy enough to lose her footing.

Sandy went back to the kitchen and collected a torch from the drawer in the table. It had been there from the time when every house had its own generator, which only ran for a couple of hours in the evening. Outside, he felt the chill of the mist and drizzle, biting after the heat of the Rayburn. It must be nearly midnight. His mother would be wondering where he was. He walked round the house. Here was the shed where Mima brought in the cow for milking. Once his eyes adjusted to the dark there was enough light spilling from the house for him to see quite clearly where he was going. He’d left on the bathroom light and the window faced this way. No need yet for the torch. The hens were already shut up. He checked the catch on the wooden henhouse and could hear the rustle of movement inside.

Earlier the day had been fine and Mima must have done her washing. The line stretched away from the house down towards where the archaeologists had set up the dig. There were still towels and a sheet pegged to the nylon rope. They hung lifeless and heavy, like the sails on a becalmed boat. Other island women would have taken down the washing as soon as the weather closed in, but Mima would probably not have bothered if she’d been eating her tea or reading a book. It was this fecklessness that so irritated some of her neighbours. How could she not care what people were thinking of her? How could she keep such an untidy house?

Sandy walked past the washing to where the students had been working. A couple of poles with string stretched between to mark out the search area, or maybe for measuring. A windbreak made of blue plastic strung on to metal stakes. A pile of turfs, neatly stacked, and another of soil. Two trenches cut at right-angles. He flashed the torch into them, but they were empty apart from a couple of puddles of water. It occurred to him that the area looked like a crime scene in one of the programmes his grandmother liked to watch.

‘Mima!’ he shouted. He thought his voice sounded very thin and high-pitched. He hardly recognized it.

He decided he should go home, switched off the torch and started back to the house. He could phone Utra from there. His mother would know where Mima was, she knew everything that happened on Whalsay. Then he saw that a coat had fallen from the line and lay in a crumpled heap on the grass. He recognized it as one of the students’ waterproofs and thought Mima had probably offered to get rid of all the mud for them. He was going to leave it: wouldn’t it need to go through the machine again anyway? But he stooped to pick it up and take it inside.

It wasn’t just a coat. It was his grandmother, looking very small inside the yellow jacket. He thought she was hardly bigger than a doll, thin, her arms and legs like twigs. He touched her face, which was cold and smooth as wax, felt for a pulse. He supposed he should call for the doctor, but he couldn’t move. He was frozen, paralysed by shock and by the need to take in the information that Mima was dead. He looked down at her face, chalk white against the muddy ground. This isn’t Mima, he thought. It can’t be. There’s been some terrible mistake. But of course it was his grandmother; he looked at the ill-fitting teeth and the wispy white hair and felt sick and very sober at the same time. He didn’t trust his judgement though. He was Sandy Wilson, who always got things wrong. Maybe he’d fumbled for the pulse and she was really alive and breathing fine.