I pocket my phone and finish my breakfast standing at the kitchen counter. I wash the last two bites of my flatbread and cheese down with a swig of lukewarm coffee, then pour a fresh cup for my wife and leave it on the table.

The cold seizes me the second I step out onto the porch. Sheets of ice line the foreshore like the cheeks of a sea with a beard of snow. My frost-covered kayak is ready and waiting for me on the jetty, but I probably won’t have time before the sun sets at around three to get out there and paddle until the pain erases everything.

My wife and I share this need to be at one with the water every day. Freyja swims daily, and even at night. How many times have I seen her shivering body swallowed up by the black water before returning to me as if risen from a casket?

With a loud yawn, and stepping around the icy puddles, I walk across the garden to the narrow steps that lead to the jetty where our little runabout is tied up, covered with a sprinkling of snow. The boat’s engine sputters to life, and I sound just like it as I clear the burning-cold air from my throat.

A few hundred metres of inshore waters are all that separate Djursholm, where I live, from Rödstuguviken, where I’m expected – a bay in the small community of Sticklinge, at the north end of the island of Lidingö. The crossing only takes a few minutes, and soon I’m tying the boat up by the red wooden cottage that gives the cove its name.

The area has already been cordoned off to keep the rubberneckers at bay. There’s more of them than I’d have thought, given the early hour. Not to mention those scoping out the scene from their balconies or from behind their windows. And it’s quite the scene.

‘Hej.’ Alvid’s there to greet me. He’s the head of the NFC – the crime-scene team. He’s wearing his trademark white coveralls. ‘I figured we had no choice but to call you in for this one,’ he says by way of apology, pursing his lips.

I give him a friendly pat on the shoulder and walk with him down the jetty to the tent the NFC has erected on the small beach, a few metres up from the frozen water’s edge.

‘I’ll be with you in a second. I’m just going to have a word with these ladies first,’ I say, leaving him to go into the tent alone.

I walk over to a trio of seniors who are standing around chatting on the road by the red cottage.

One of them has a stripy beanie on her head. ‘Are you Detective Inspector Rosén?’ she asks me.

I nod.

‘See, Ilse, I told you it was him,’ she says to the woman to her left, who’s wearing a fur hat.

‘They told us we could put our clothes back on,’ the woman continues, turning back to me. ‘But I do wonder if that was the right thing to do.’

I look at her, uncomprehending.

‘The problem, Inspector,’ her friend Ilse explains, ‘is that the rest of your team here are still wet around the ears. Just look at them.’ She points to my officers, who are all hard at work. ‘I really don’t know if we should have listened to them. I mean, shouldn’t they have taken our … oh, my brain is getting so old, I don’t know … our fingerprints, that’s it!’

‘Assuming you didn’t touch the body, then no,’ I reply, only half joking.

‘Of course we didn’t. Heaven forbid!’ the third woman chimes in, pressing her palms to her chest.

‘And that wouldn’t have been an easy thing to do, obviously,’ Ilse adds. ‘She was trapped in the ice.’

I nod, appreciating the logic of her comment. ‘Can you tell me how you found the body?’

‘We were getting ready to go for a dip around eight, as usual, just the kind of thing to smooth out the wrinkles and wake up the heart,’ the third woman explains. ‘We swim here every day. There’s a few more of us on the weekend, but during the week it’s just the three of us besties from Braxenvägen. That’s the street just behind the house with the turret up there, see?’ She points to a building painted green and Falu-copper red. ‘Normally, we go into the water from the beach, where you’ve pitched your tent. But when the sea’s frozen over like it is today, we go in by the jetty, where you’ve moored your boat. Sometimes we have to poke a hole in the ice, or if it isn’t that thick, we just slide into it. It’s not that hard.’

The two other women nod.

‘And that was when we saw her.’

‘But we didn’t think it was – how should I put it? – a woman,’ Ilse continues. ‘We thought it must have been a mannequin or something. You know, the things you see in shop windows. With her pale skin, those glassy eyes, that dull blonde hair and those long slim legs of hers – and stark naked too. So we stood there looking at her for a while through the ice, cursing the hooligans who’d throw such a thing in the sea. We wondered how the heck we were going to get it out of the water.’

‘What did you do when you realised it was a … a body,’ I ask, making sure to soften my words.

‘Ilse thought we should try to get her out of the water,’ says the swimmer with the stripy hat, ‘but I told her there was no point. She looked dead enough to me, so I said we’d better call the police.’

I nod robotically, quite surprised by their composure.

‘Did you see anyone else in the area?’

‘Of course. Everyone’s on their way to work or school at that time.’

‘Did you notice anyone you didn’t recognise?’

They shake their heads in unison.

‘Thank you, ladies. You’re almost free to go. An officer will take a quick statement from you and a psychologist will be in touch.’

They turn and stare at me, their eyes like dinner plates.

‘A psychologist? Whatever for?’ Ilse asks.

‘To help you, er … to talk to you about the shock of what you found.’

‘Don’t you worry, Inspector, we’ll talk about it among ourselves. And with our swimming club friends this weekend. If there’s one thing you can be sure of, it’s that we’re going to talk about this!’

‘I don’t suppose we can go for a swim now?’ one of the other women pipes up.

‘You can, just not here in Rödstuguviken,’ I reply, thinking this intrepid trio and their nerves of steel would put many of the recruits on the force to shame.

I thank them again and duck back under the crime-scene tape to pull on the coveralls that one of my sergeants has ready for me. Then I enter the tent where the NFC officers are working in a silence broken only by the swishing of their protective gear.

The victim is lying on a stretcher.

‘Fifteen, maybe sixteen years old,’ Alvin says, joining me beside the body.

I shake my head.

I don’t have kids, and I probably never will. Still, nothing wrenches my heart more than the death of a child. The parents always die with them. It’s like they’re uprooted by their loss. The grief drains the life from them, even if they have other kids to support. And it’s not just the mothers who suffer. Sometimes the fathers are the first to lose their grip. They let themselves go and forget about the others who have also been left behind – those cursed to go on living in the wake of a sister or brother who’s never seemed more alive than in death.

‘She wasn’t in the water for long,’ Alvid explains.

It certainly doesn’t look like the sea and its creatures have had enough time to make a mess of the body. It’s frozen and blue from the cold – the temperature went down to minus eleven last night – which makes this death a little easier on the eye, at least for now. Her hair is soaking in a puddle around her head. It strikes me that the ladies who found her were right – to look at her, there’s nothing really human left. Rather, there’s something ethereal and intangible about her, as if I’m in the presence of one of Tolkien’s elves.

My gaze lands on the wounds on the insides of her thighs. Sealed and solidified by the cold, they look like two big claw marks.

‘Like I said,’ Alvid sighs. ‘We really needed you here.’

‘I know.’

‘Are you going to be all right?’ he asks, not daring to look at me.

‘I’ll be all right.’

Alvid nods and points to the pair of scissors attached to a leather cord around the victim’s neck. They’re now resting on the stretcher above her shoulder.

‘So, did those grannies see anything?’ he asks.

‘No, nothing at...