It was the alien that made Mayumi's Grandma into a detective.

'Not just any detective,' says Grandma. 'The Great Detective.'

'Obāchan, you have an inflated sense of your own importance,' says Mayumi.

But Grandma just smiles, and goes off to do some detecting.

When the snow melts and the blossoms are out along the riverbanks, Mayumi decides it is time for Grandma to start being nice to Kenji. It isn't easy, having the Great Detective in the family. Social occasions are sometimes strained.

'It just takes her a while to warm to people,' she says to Kenji as they cross the bridge over the river. 'It's nothing to do with you personally.'

Grandma is already in the park, drinking sake and peering at her neighbours.

'It feels personal,' mutters Kenji. Grandma spots them and waves a sake bottle that looks, to Mayumi, suspiciously empty.

She was six when she first learned that her Grandma was the Great Detective, just after the bad time, after Grandma took her home from the hospital and gave her sweet mochi and said, 'It's just us now, Yumi-chan.'

Mayumi thought everyone's Grandmas could find the lost things, the things dropped on the way to school or hidden in the backs of wardrobes. She thought everyone's Grandmas constantly watched reruns of The Adventures of Sherlock Holmes from the BBC dubbed into Japanese and knocked on strangers' doors to return thin bands of gold or crumpled photographs. Sometimes Grandma made people happy, but sometimes they were sad, and Mayumi didn't understand why.

This was before she knew about the alien.

'Sake?' Grandma proffers the bottle, fixing Kenji with that piercing look that Mayumi knows all too well.

'Thank you, none for me if you don't mind,' says Kenji, 'Gives me indigestion. The doctor said I should stay away from liquor.'

Mayumi tries not to look at Grandma's expression.

'So,' says Grandma, after a pause. 'How are the kitties?'

Kenji and Mayumi work for a company making maneki-neko, beckoning cats, who all wave and smile blankly, and remind Mayumi just a little bit of Kenji. 

'We've released a new spring design, actually,' says Kenji, rummaging in his bag. 'Would you like to see—'

'Ah,' says Grandma, suddenly. 'Those documents—I know where they are.'

Mayumi sighs.

'Over there, on the bench,' says Grandma. 'It's that little man from the office, Nakata, the one who sweats too much. They're right there in his briefcase. Hmpf, probably wants to pass the work off as his own. I'd better go and talk to him.'

'Obāchan, no! Don't make a scene,' says Mayumi, quickly.

'It's fine, it's fine,' she says, struggling to her feet. 'It's just to let him know I know.'

'How does she know?' says Kenji as they watch her totter over to the unsuspecting Mr Nakata.

Once upon a time she met an alien and it gave her superpowers, thinks Mayumi, but she doesn't say it out loud, because Kenji finds jokes disconcerting.

'She's just incredibly nosey and good at guessing,' she says, sipping her sake. 'I think it's what happens when you get old.'

'Really?' says Kenji, and they watch as Mr Nakata sheepishly hands a bundle of papers to Grandma.

'Really,' says Mayumi, though she has never, ever been sure.

The alien asked Grandma what she wanted most in the whole world.

'And what did you want, Obāchan?' asks Mayumi, every time she hears the story.

'I wanted what everyone wants, Yumi-chan,' says Grandma. 'I wanted things to be better.'

But Mayumi has always puzzled over the alien's strategy for achieving this.

'It's just that detectives are so…' she begins.

'What?' demands Grandma.

Mayumi pauses. 'Damaged,' she says, finally. 'In stories, anyway. Sad. Weighed down by the world.'

Grandma shrugs. 'Knowing the truth, it's not easy. Finding out about the lives of others.'

She says she didn't think the alien would actually do what she asked. She says she thought the same rules applied to aliens as to human men.

'And what are they?' asks Mayumi.

Grandma raises her eyebrows. 'That they'll promise you anything. That the truth isn't important.'

But it seems that aliens keep their promises.

At the summer festival Mayumi's yukata is decorated with yellow lanterns and pink blossoms. She tries to suck her tummy in whilst Grandma ties her obi for her.

'You need to learn to do this yourself,' says Grandma. 'I've told you about when I met your grandfather…'

She has. Many times. 'Tell me again, Obāchan,' says Mayumi.

'I was twenty… At the festival I'd tied my obi wrong, and it came loose. I had to run behind the trees to put myself together again, all my friends were laughing too much to help. And he was there, leaning against the trunk of a tree and smoking a cigarette. So I was half-undressed the first time I met my husband.' She grins a wicked grin. 'And in those days, people were easily shocked. But not, as it turns out, your grandfather.'

Grandfather was a salesman, driving around Japan selling electric shavers, until the day he crashed his car in a snowstorm, a long way away from here.

From his picture on the living room shrine Mayumi thinks he looked like a Hollywood matinee idol.

'All my friends were jealous,' says Grandma. 'He was like something from a different world.'

'He loved you,' says Mayumi.

Grandma smiles. 'He was too good to be true,' she says.

Lanterns hang from the tall arches of the bridge, its reflection in the water making an eye rimmed with gold. Fireworks light up the sky in reds and greens. In the park, amongst the stalls and rides, Grandma greets almost everyone by name. She can talk to anyone, anyone at all, which is as much of a mystery to Mayumi as anything else.

Mayumi wins a goldfish by fishing for rubber ducks in a paddling pool. By the banks of the river taiko drummers are performing, the intensity of their rhythms making the night air electric. One of the taiko drummers winks at her. He is wearing tiny shorts and a sleeveless jacket and sweat has plastered his hair to his forehead. Mayumi looks away.

'He's the one,' says Grandma, elbowing her in the ribs. 'Forget that weakling. There's the man for you, girl.'

'How can you possibly know that? Anyway, I wish you'd be nicer to Kenji.'

'I'm the Great Detective,' says Grandma, in insulted tones. 'I've been investigating your problem for some time now.'

Mayumi maintains a dignified silence. Really, sometimes there's no point arguing with her.

In Mayumi's head the alien is always changing. One moment it is a little green man, with an elongated head and huge black eyes. The next moment it looks like her grandfather. The next it is spindly and tree-like. 

Grandma's own story changes every time. She calls the alien 'it.'

'But why was it here?' says Mayumi, helping Grandma prepare dinner. 'What was it doing?'

Grandma shrugs and keeps cutting up the daikon. It is one question she never has an answer for.

 'Well, why did it leave? Where did it go? Aren't you angry?'

Grandma gets a faraway look in her eyes.

'It's different for them,' she says. 'Simpler.'

Grandma tells her she should always ask questions, that she should always try to find out the truth. But, thinks Mayumi, maybe sometimes the truth isn't what you want at all. Maybe sometimes it's better not to know.

When she lights incense for her mother in front of the shrine she asks Grandma what she was like when she was a little girl. Grandma says she was such an ugly baby she used to cover the pram with a blanket when they went out.

'She grew up to be beautiful, though,' she goes on. Then stops, and looks away.

Mayumi doesn't ask about her nameless father, though. She doesn't ask about the illness, just a year after grandfather died. She doesn't ask how Grandma managed when she was left to bring up a six-year-old grandchild all alone.

She doesn't ask if that was why Grandma thought she met an alien.

The taiko drummer's name is Seiji. At the festival Grandma somehow managed to give him Mayumi's number and he starts inviting her to dinner and karaoke. She always says no. She would rather stay at home and watch reruns of Detective Saito on the Mystery Channel with Grandma.

'I keep telling him I have a boyfriend,' says Mayumi. 'But I'm not sure it's going in.'

'He's doing it all wrong,' shouts Grandma at the television. 'I solved it half an hour ago.'

Detective Saito is a college student who solves crimes. Grandma says he isn't half as clever as he thinks he is.

'You haven't been out with that weakling for ages. I knew your heart wasn't really in it.'

'Don't call him that,' says Mayumi. 'He's lovely. He's—'

'—got the conversational skills of a goldfish. You need to get out more, my girl,' says Grandma. 'Watching TV is for old people. I've earned it. You haven't.'

'You want me to go out and drink beer in unsavoury places with a man I don't actually know?'

Grandma grins. 'I wish I'd gone out and drunk beer in more unsavoury places. Young people are so lucky these days.' She shoots a sideways look at Mayumi. 'You should meet more people. I'm not going to be around forever.'

Mayumi gets a sick feeling in the pit of her stomach. She doesn't want to meet more people; she doesn't have Grandma's obsession with the lives of others. She wants things to stay as they are. Without Grandma, she will come unmoored.

In autumn the pumpkins in Asahikawa grow big enough to make an armchair. There are photos of Mayumi sitting on one when she was very small. A tiny child on a huge orange throne. Her grandfather is beside her, ready to catch her if she fell off.

'He adored you,' says Grandma. 'He was better with you than with your mother when she was little. I think he'd got the hang of it the second time round.'

But in most of the photos her grandfather isn't there.

'Always working,' Grandma says. 'Always somewhere else.'

'It must have been lonely.'

'For him or me?'

'For both of you. So far apart.'

Grandma grunts. 'Well that's just what happens, isn't it? With people.'

That's just what happens with people, thinks Mayumi. She sees Kenji at work and they smile at each other. They haven't been out for drinks since New Year. Seiji the taiko drummer has stopped ringing her. It's just what happens.

The leaves outside her window are red and gold. She puts out the autumn beckoning cat, the one that has a sadder face than the others. She turns it to the window so it will beckon the good fortune from outside.

Except the beckoning cat doesn't beckon good fortune this time.

In the autumn Mayumi's Grandma dies.

Before she dies she says to Mayumi, 'You'll have to be the Great Detective now.'

Mayumi nods and holds her Grandma's hand and doesn't look her in the eye. They've been watching an anime series called Poirot and Marple. There is an annoying girl and a cute bird in it. Grandma says they shouldn't have made Agatha Christie cute. Mysteries aren't cute, she says, they're serious. That's the whole point. They watch it anyway, even though it's wrong.

The bedroom is full of flowers and cards and soft toys from all the people Grandma knows.

'I mean it,' says Grandma. 'Don't look like that. I know exactly what you're thinking.'

Mayumi gulps down a sob. 'How on earth do you know so many people, Obāchan? Half the town must have sent you cards.'

Grandma ignores her. 'It isn't going to be easy,' she says. 'It'll take some getting used to. People don't always want to find out the truth.'

'You did,' says Mayumi, trying not to sniff.

'Well, I'm made of strong stuff,' says Grandma. From somewhere within her voluminous nightclothes she takes out a pin and before Mayumi can stop her she stabs it into her finger.

'Obāchan!'

'Kiss it better,' says Grandma, unperturbed.

'What?'

Grandma holds out a shaky hand, blood pearling on her finger. 'Go on,' she says.

Mayumi is filled with a sudden, terrible urge to laugh, bubbling up from her belly. But she takes her grandma's hand and kisses it, tastes blood.

Grandma smiles. 'There,' she says, and lies back on the pillows. 'There,' she says again, and the Great Detective closes her eyes.

During the wake, Mayumi is convinced that Grandma is about to walk through the door, even though her body is lying there in a white kimono. After all, she is sure the Great Detective is a faker.

When everyone has gone she looks through all of Grandma's things. The beckoning cats all hold their arms still and watch her whilst she works. There is surprisingly little, for such a long life. She unfolds Grandma's kimono from their tissue paper, holds them up to herself in the mirror. She packs away Grandma's battered detective novels. She takes out her futon and drapes them out of the window to air. As she is about to close the cabinet doors she sees a box, tucked right at the back. In the box there are letters addressed to her grandfather, written in a hand she doesn't recognise, from a woman, it turns out, called Ayako.

Mayumi sits on the floor and reads the letters. She reads them a second time. Then very carefully, she puts them all away again and puts the box back. In another box, she finds postcards from Grandfather, postmarked from all over Japan, pictures of gardens in Kyoto, of deer in Nara, of a white castle in Himeji. On the back of the cards he has written to Grandma, I miss you, I'm thinking of you.

Mayumi wonders when Grandma first knew he was lying.

Her colleagues tell her she should get a pet. 'To make the house seem less empty,' they say, sympathetically. But Mayumi is allergic to cats, and dogs are so difficult, always needing.

'I'm fine,' she says to everyone. 'I'm fine. Thank you for asking.'

When she walks home past couples and families and friends, arm in arm, hand in hand, she is afraid that she might float away, with nothing to anchor her to the earth.

In winter the soldiers from the army base come to build a giant snow sculpture by the river. This year the sculpture is a great snow palace with a dragon draped over the turrets. Mayumi watches the palace go up as she walks over the bridge every day to work. She has always loved the snow festival, the river frozen and the sculpture rising up beside it. She and Grandma would stand on the bridge and watch the soldiers, Grandma making up outrageous stories about them that she always insisted were true. Mayumi blinks away tears but they freeze to her eyelashes.

On the night of the festival she stops on the bridge, letting the crowds push past her. The park has been transformed into a forest of frozen things, ice animals and ice people; ice trees, their silver branches impossibly still. The taiko players must be freezing, they are holding their batons with their bare hands, their breath hanging in clouds before them. She recognises Seiji, who catches her eye and smiles, and she imagines Grandma beside her, elbowing her, telling her to wave. But as she is raising her arm she stops.

Something is happening to the air around him, creating a reddish haze. She blinks; it must be her eyes. Hurrying from the bridge she pushes through the crowd until she sees him clearly. Her breath catches in her throat. The haze all around him has become tendrils, red and warm, and they are stretching towards her, floating gently on the cold night air.

Mayumi reaches out her gloved hand. The tendrils greet her, tentative at first, then pushing towards her eagerly, wrapping around her gloved fingers. She looks around at the crowd, but noone else is watching, noone else sees the hazes, the tendrils all around them. Some are warm reds and oranges, others are silvery white, almost lost in the snow. Still others resemble iron barbs. They float out in different directions, some reaching another person, some vanishing into the distance.

Mayumi takes off her glove to touch one of the delicate red tendrils seeking her hand. It is warm and silky and dissolves at her touch. Seiji catches her eye and smiles. And without thinking, Mayumi smiles back.

A yellowy golden thread ties the woman next to her to the young child beside her, begging to be picked up to see the drumming better. When she holds him in her arms the thread floats gently around them both and Mayumi feels a tightening in her stomach.

As the performances finish it begins to snow more heavily. Seiji appears out of the whiteness. 'I'll walk you home,' he says.

'I live just across the bridge,' says Mayumi, distracted. 'It's fine, really.'

'Okay.' He gives an awkward nod and scratches the stubble on his chin. 'Maybe another time.'

She hesitates, fascinated by the changing colours around him, and as she's staring, he leans in towards her, and as he leans in there is an awkward moment.

They stumble apart. He smiles, shyly, then turns around and walks away through the snow. The tendrils trail behind him, reaching out towards Mayumi.

The snow is falling harder as she walks up the steps towards the bridge. She looks behind her, but the ice palace has disappeared into flakes tinged orange by the street lamps, seeming to fall in different directions, dancing in the air all around her. The snow sucks the world into itself. Sound changes. Direction disappears. She is alone in the orangey white and the silence hurts her ears.

That's when she feels the ground beneath her feet move. She looks up through the snow at the high arches of the bridge and sees that they are breaking; the bridge is falling, it must be, but the arches are falling the wrong way, reaching up into the sky like many spindly arms, and the bridge is rising, staggering to its feet, a great, many-limbed creature, its joints cracking like gunshots. Further and further it rises, unfurling into the unstill night.

Mayumi falls to her knees.

Through the snow are bright ribbons of red and gold.

A thin, tentative thread moves towards her, first pale pink then growing to brighter red. The thread wraps around her, slowly, as if testing, as if unsure. When it touches her cheek there is a slight warmth.

She feels something that she recognises as relief.

'Hello?' she says.        

From within the snow, something moves. Mayumi hesitates. The tendril wavers.

Then she says, very carefully, 'I'm honoured to meet you.'

The tendril becomes a brilliant red. Mayumi imagines Grandma beside her on the bridge, muttering, Finally.

She edges a little closer. A shudder in the snow, a flash of anxiety from the tendrils. 'It's all right,' she says. 'I know… I think I know—'

She knows. Of course she knows. She is the Great Detective, and she understands the truth. She can follow the tendrils and read the clues her Grandma used to read, the clues that told her about what was wanted and what was loved, that told her about the bad things and the lost things and the terrible, terrible loneliness of a hidden creature on a bridge.

'She always said… but I didn't believe her. Not really.'

She looks closer but even though the snow is falling more lightly now the alien is too cleverly disguised, too perfectly blended with the bridge. A chameleon, here all this time, ignored. She thinks for a moment that she might have glimpsed an eye, light reflected in something huge and watery black.

It must have been waiting. It must have recognised something inside her Grandma. It must have seen that there was finally something it could do to help.

'You made her very happy,' says Mayumi, wondering how peculiar she must look if anyone passed by. 'You made it better.'

Tendrils brush her cheek, happy and sad at once. It makes her feel unsteady, such understanding, so sudden and so strong. It won't be easy, Grandma had said. It'll take some getting used to. Knowing the truth is a burden. It's also a gift.

Mayumi smiles, remembering. It's why they're all so gloomy, the detectives, said Grandma. Well, the men, anyway. And she'd sniffed, significantly.  

But the alien knows it is difficult. It retreats, just a little. It reaches out its tendrils gently. And it shows Mayumi that she is not alone.

It shows her how the Great Detective discovered her trade. It shows her a hard night twenty years ago, a woman walking home through a storm, wishing her life were different. A fall about to happen. (Was it deliberate? thinks Mayumi. Did she want to fall? A lost husband, a lost child, an old railing, an accident waiting to happen.) But there was something there, something to reach out strange arms to catch her when she came unmoored. A secret, hidden thing that wanted to help, that understood the truth.

That understood what truth could do.

The alien had led her Grandma to the side of the bridge, to sleep that night curled up beside it, beneath limbs arched above her to keep her dry. And in the morning, before the world woke, the alien kept its promise.

It is time to leave. She can't tell how much time has passed but the snow has stopped and there are people venturing out into the night again. The bridge is just a bridge. But still, in the air, faint ribbons, tendrils floating up into the night. Mayumi makes a low bow, but before she goes she says, 'She didn't really need to do the thing with the needle and the blood, did she? That was just… dramatic tension.'

The tendrils shimmer. And Mayumi knows that the alien is laughing.

Spring, and the cherry blossom hesitates on the branches. Mayumi sits on a blanket with Seiji, watching the people in the park. Tendrils reach out and twine around them, around the lovers and the jealous and the sad, around keys dropped in the grass, around faded photographs in wallets.

Over the river the bridge squats, watchful. Where the water ripples the eye winks. 'You should wink back,' Grandma always said. Mayumi can see where the air around it wavers, where the alien is reaching out to feel their little, human lives. Where their little human lives make the alien feel less alone. Part of it reaches out to her, the lightest of touches, as if just to tell her it's there.

People come up to her. They ask her to find things they have lost: car keys, wedding rings, pets, people.

It isn't easy being the Great Detective. She wishes her Grandma was still here. She wishes she was sitting on the blanket, swigging sake from the bottle and fixing their neighbours with a beady eye.

'She'd be proud,' says Seiji. His own pride curls around her, the colour of autumn leaves, warm and strong. 

She'd be smug, thinks Mayumi. She'd grin that irrepressible grin and say I told you so.

The Great Detective's work is never done. But there are times, thinks Mayumi, when it will just have to wait. When the Great Detective needs a moment to herself. She lies back, her hands behind her head and legs draped over Seiji's. The blossoms above are impossibly bright and all around her are threads of every colour, weaving her own life into the lives of others.