Joona groans as he turns round, strikes low with the stick, then jabs behind him before he stops and looks into Erik's face.

His face is wet with sweat, his muscles are pumped with blood and he's breathing hard, but isn't exactly out of breath.

'Have you had time to look into your old patients?'

'I've found a few who were the children of priests,' Erik says. Then he hears a car pull in and stop at the front of the house.

'Give their names to Margot.'

'But I've only just started going through the archive,' he says.

Nelly walks round the house, waves, and comes over to them. She's wearing a fitted riding jacket and tight black trousers.

'We ought to be at Rachel Yehuda's lecture,' she says, sitting down next to Erik.

'Is that today?'

Joona's phone rings and he walks over towards the shed before answering.

It strikes Erik that Nelly seems tired and subdued. The thin skin below her eyes is grey and she's frowning.

'Can't you report yourself?' she asks.

'I've thought about it.'

She just shakes her head and looks wearily at him.

'Do you think my mouth is ugly?' she asks. 'Your lips get thinner as you get older. And Martin ... he's very sensitive when it comes to mouths.'

'So how does Martin look, then? Hasn't he got older?'

'Don't laugh, but I'm thinking of having surgery ... I'm not prepared to get older, I don't want anyone thinking he's being kind by sleeping with me.'

'You're very attractive, Nelly.'

'I'm not fishing for compliments, but that's not the way it feels, not any more ...'

She falls silent as her chin starts to tremble.

'What's happened?'

'Nothing,' she says, gently rubbing beneath her eyes before looking up.

'You need to talk to Martin about those p.o.r.n films if it's upsetting you.'

'It isn't,' she says.

Joona has finished his call and is heading towards them with his phone in his hand.

'The Slavic Inst.i.tute have managed to decipher the lettering on that watch. The writing's Belarusian, apparently.'

'What does it say?' Erik asks.

'In honour of Andrej Kaliov's great achievements, Military Faculty, Yanka Kupala University.'

They follow Joona into the study and listen to him as he tracks the name down in less than five minutes. Interpol has one hundred and ninety member countries, and he is put through by the unit for international police cooperation to the office of the National Central Bureau in Minsk.

He finds out that there's no indication that Andrej Kaliov is missing, but that a woman by the name of Natalia Kaliova from Gomel has been reported missing.

In British-accented English the woman on the phone explains that Natalia the woman Rocky called Tina was believed to have been a victim of human trafficking.

'Her family say that a friend of hers called from Sweden and encouraged her to go there via Finland, without a residence permit.'

'Is that everything?' Joona asks.

'You could try talking to her sister,' the woman says.

'Her sister?'

'She went to Sweden to look for her big sister, and is evidently still there. It says here that she calls us regularly to find out if there's any news.'

'What's the sister's name?'

'Irina Kaliova.'

79.

The central kitchen of the NBA on Kungsholmen in Stockholm smells of boiled potatoes. The cooks are standing at their stoves dressed in protective white clothing and hairnets. The sound of a slicing machine echoes off the tiled walls and metal worktops.

Erik asked Nelly to go with them to meet Irina Kaliova. It could be useful to have a female psychologist on hand when the woman finds out that her sister had been a victim of the s.e.x-trafficking industry before she was murdered.

Irina is dressed like all the others, in a hairnet and white coat. She's standing by a row of huge saucepans hanging from fixed hooks. She's staring at a display panel with a look of concentration, taps a command and pulls a lever to tip one of the pans.

'Irina?' Joona asks.

She lifts her head and looks inquisitively at the three strangers. Her cheeks are red and her forehead sweaty from the steam rising from the boiling water, and a strand of loose hair is hanging over her brow.

'Do you speak Swedish?'

'Yes,' she says, and carries on working.

'We're from the police, the National Criminal Investigation Department.'

'I've got a residence permit,' she says quickly. 'Everything's in my locker, my pa.s.sport and all my doc.u.ments.'

'Is there somewhere we could go and talk?'

'I need to ask my boss first.'

'We've already spoken to him,' Joona says.

Irina says something to one of the women, who smiles back. She puts her hairnet in her pocket, then leads them through the noisy kitchen, past a row of food trolleys and into a small staffroom with a sink full of unwashed mugs. There are six chairs around a table with a bowl of apples at its centre.

'I thought I was about to get the sack,' she says with a nervous smile.

'Can we sit down?' Joona asks.

Irina nods and sits on one of the chairs. She has a pretty, round face, like a fourteen-year-old. Joona looks at her slender shoulders in her white coat, and finds himself thinking of her sister's white skeleton in the grave.

Natalia used the name Tina as a prost.i.tute, and she was murdered and buried like so much rubbish because she was alone, had no papers, and no one to help her. She was used up by Sweden, and afterwards wasn't even worth the cost of proper identification.

There's nothing so hard in police work as having to inform a relative about a death in the course of an investigation.

There's no way to get used to the pain that fills their eyes, the way all the colour drains from their faces. Any attempt to be sociable, to laugh and joke vanishes. The last thing to go is an effort to appear rational, to try to ask sensible questions.

Irina gathers together some crumbs on the table with a trembling hand. Hope and fear flit across her face.

'I'm afraid we've got bad news,' Joona says. 'Your sister Natalia is dead, her remains have just been found.'

'Now?' she asks hollowly.

'She's been dead for nine years.'

'I don't understand ...'

'But she's only just been found.'

'In Sweden? I looked for her, I don't understand.'

'She had been buried, but couldn't be identified before, that's why it's taken so long.'

The small hands keep moving the crumbs, then slip on to her lap.

'How did it happen?' she asks, her eyes still wide-open and empty.

'We're not sure yet,' Erik replies.

'Her heart was always ... she didn't want to worry us, but sometimes it would just stop beating, it felt like an eternity before it ...'

Irina's chin begins to tremble, she hides her mouth with her hand, looks down and swallows hard.

'Have you got anyone to talk to after work?' Nelly asks.

'What?'

She quickly wipes the tears from her cheeks, swallows again and looks up.

'OK,' she says, in a more focused voice. 'What do I have to do, do I have to pay anything?'

'Nothing, we'd just like to ask a few questions,' Joona says. 'Would that be OK?'

She nods, and starts picking at the crumbs on the table again. They hear a metallic sound from the kitchen and someone tries the door.

'Did you have any contact with your sister while she was in Sweden?'

Irina shakes her head, her mouth moves slightly, then she looks up.

'I was the only person who knew she was heading to Stockholm, but I promised not to say anything. I was young, I didn't understand ... She was very stern with me, said she wanted to surprise Mum with her first wages ... Nothing ever came, but I spoke to her on the telephone once, she just said that everything would be all right ...'

Irina falls silent and drifts off.

'Did she say where she was living?'

'We haven't got any brothers,' she replies. 'Dad died when we were little, I don't remember him but Natalia did ... and after Natalia had gone, there was just me and Mum left ... Mum missed her so much, she used to cry and worry about her weak heart, and said she just knew that something terrible had happened. So I thought if I could find my sister and take her back home, then everything would be fine ... Mum didn't want me to leave, and she was alone when she died.'

'I'm so sorry,' Joona says.

'Thank you. Well, now I know that Natalia is dead,' Irina says, getting to her feet. 'I suppose I suspected as much, but now I know.'

'Do you know where she was living?'

'No.'

She takes a step towards the door, clearly keen to get away from the whole situation.

'Please, sit down for a moment,' Erik asks.

'OK, but I need to get back to work.'

'Irina,' Joona says, with a dark resonance in his voice that makes the young woman listen. 'Your sister was murdered.'

'No, I just told you, her heart-'

Irina's coat catches on the back of the chair, dragging it backwards with her. As the truth sinks in, she loses control of her face. Her cheeks turn white, her lips quiver and her pupils dilate.

'No,' she whimpers.

She leans back against the worktop, shakes her head, fumbles across the front of the fridge for something to hold on to. Nelly tries to calm her down, but she pulls free.

'Irina, you need to-'