I lean forward on the icy ferry rail, as the white coils of mist slowly unravel ahead of us.

And finally … there it is. The island of Langer. Our new home.

All the other passengers on this little ferry have stayed in their cars, safe from the intense cold. Calder and I are the only idiots watching the approach from outside, clearly newcomers. Well, I am. Calder was born here, but left twenty-odd years ago. I look up at him, his long black hair flapping in the wind, his cheeks ruddy and his forehead scrunched, with little lines puckering at the corners of his eyes. Is that from the cold? Or from memories of his childhood here?

‘You OK?’ I call, pitching up over the wind.

He nods, not taking his eyes off the island.

I glance down and notice a fat seagull bobbing on the surging water below us. Aren’t its feet freezing in that cold sea? Yet it looks totally unperturbed, all puffed up and full of itself.

The A4 typed timetable on the quay noticeboard said that the journey to this slate island off the west coast of Scotland would take fourteen minutes. That sounded short, but it feels much longer in this bitter buffeting. How can it be this sunny and yet still so brutally cold? Our rental car is parked in the base of this little ferry, cleverly packed in with five other cars by the burly man in a tight brown jumper who waved us on. But we’ve come outside to the metal ramp on the side of the boat, at my insistence. I want to enjoy every moment of our approach, however glacial it is.

The fat seagull abruptly dives down, instantly invisible in the grey depths. I wait for it to resurface, but it’s nowhere to be seen. I keep on scanning the water, but it doesn’t come back up.

‘Where’s that bird?’

‘What bird?’ Calder asks distractedly.

‘A seagull. It was just there,’ I say, pointing. ‘I was looking right at it and it suddenly ducked under, and disappeared entirely.’

‘Oh, Nancy, it’ll be fine.’

‘But how long can it survive down there? That water must be freezing.’

He turns to face me and raises an eyebrow. ‘I sincerely doubt that some bird has decided to end it all just ’cos you were staring at it. Then again, you do have an impressive stare, sooo …’

‘Yeah, all right,’ I laugh. But as he looks back at the island, I drag my thin coat sleeves over my bitten fingernails to grip the railing, then lever myself over it as far as I dare, to scan the water.

‘Hey, be careful,’ Calder yelps, pulling me back.

‘I’m fine,’ I laugh. But where is that bloody bird? The poor thing must be dead by now. Though if it is, why hasn’t its frozen carcass bobbed up yet? I inhale the cold briny air as I stare down at the ever-changing pattern of fine lines on the surface of the water. Can it have swum down deep, right under the ferry? I turn and look back. No sign of it. Only the furrow of white frothing water the ferry is leaving behind in its wake, just as we’re leaving behind our old lives. And everyone in them.

Oh please, come back up, you stupid bird. This is surely a bad omen for our move.

But there’s no sign of it. It’s dead. Of course it is. Life is so fragile. If you don’t stay alert, hold on really tight, boom, it’s gone in an instant.

Suddenly the bird pops up right in front of me, shaking itself free of water, all jaunty and smug. Oh, thank God. It cocks its head and locks its beady eyes on me for a moment, regarding my relief with a withering look. Then it merrily bobs off on the undulating water. Everything’s fine.

My breath puffs out into the icy air as I return to watching the island coming into view. The mist has now curled around and re-formed behind us, erasing where we’ve come from. But the white coils up ahead have completely cleared, to present the island to us in all its glory. Before I met Calder, I’d heard of the Hebrides, Skye and Mull but always assumed that there were only about twenty or thirty islands dotted along the coast of Scotland. But I now know that there are over nine hundred. Ninety-five of them populated. Some with a few thousand people and some with less than a hundred, like this windswept beauty. It’s long and tapering, comprised of endless curves and planes of different angles and painted with every gradation of grey, green and brown imaginable. It looks like a dappled sleeping monster, half submerged in the grey sea and basking in the sun. To the right of the small bricked dock ahead is a slate beach, which hardly fits any category of ‘beach’ I’ve ever known or imagined. It’s an awesome expanse of glinting angles, endless jagged grey shards, as if this huge gunmetal sea all around us had risen up into the air, frozen, and then exploded all over the shore.

‘It’s amazing,’ I whisper.

Calder takes a sudden breath as he snaps out of his strange trance and looks down at me. ‘Excited?’

‘Totally,’ I laugh. ‘No mortgage, no boss, no commute. Just … all this.’ I gesture at the stunning rugged island. ‘What’s not to love.’

‘We’ll be our own bosses now, so I hope we’re easy to work with.’

‘Oh, I intend to be very lax indeed.’

He laughs. He’s starting his own loft extension company up here having been an employee in one for years. I’m swapping the hectic stress of being a BBC radio drama producer in London for the hassle-free simplicity of being an online film script editor. He’s asked me so many times if I’m sure about this move and I so am. More than he can possibly know.

The boat judders and goosebumps flare across me. I hadn’t realised quite how bizarre it would feel to be crossing a huge surging sea to get to our new home. Fantasising about moving to an island and actually moving to one are very different things. I’m only just now grasping that once these ferries stop running in the evenings, we’ll be totally marooned here. Which is exciting. As if we’re entering some magical guarded realm. I breathe deeply and the rush of cold air makes me dizzy. My giddiness is probably heightened by the fact that I haven’t slept for about twenty-four hours: including seven and a half hours not sleeping on the sleeper from London to Glasgow, three hours not sleeping on the local train from Glasgow to Oban, where we picked up our hire car, and half an hour not sleeping on the drive from Oban to the coast. And now we’re on the final leg, the fourteen-minute ferry ride to the island, and no one could possibly sleep in these arctic conditions. It was thrilling to get single tickets all the way. At first, I couldn’t find the option on the Trainline booking site, only returns, as if the site was saying: Single tickets to Scotland and not just to the mainland, to an isolated island, are you absolutely sure? I was. And I am. This is a completely fresh start with the only person who really matters to me any more.

‘Five pounds!’ comes a shout. It’s the burly man in the thick brown jumper who waved our car on. He’s approaching us with a black shoulder bag of money and holding a grey card-reader.

‘Of course,’ Calder says, pulling out a note from his overstuffed wallet.

‘Calder, isn’t it?’ the man asks.

‘Yes, that’s right. Hi Mr Mullins, I wasn’t sure if you’d recognised me.’

The man snorts. ‘Aye, course I did. I wouldn’t forget you, you gobshite.’

I tense, but Calder laughs.

‘And anyway, we’ve been warned to keep a look out for you. You’re the talk of the island, coming back to take over your mum’s place. Not many of our lost children come back here. Welcome home.’

They share a knowing nod.

‘Oh, and this is my girlfriend, Nancy.’

‘Pleased to meet you,’ the man mumbles, then turns and his retreating footsteps clang on the metal steps.

‘Lost children?’ I ask, once the man’s out of earshot.

‘It’s nothing sinister. It’s just the dramatic way they talk here. Lots of the young people born on the island get bored by the time they’re teenagers and leave as soon as they can. But the islanders have to guilt-trip us by making it sound sad and suspicious.’

A blast of cold air buffets me and I shiver.

‘You OK?’ Calder asks.

‘Yes, just excited – and a bit cold.’

He pulls off his huge black coat and wraps it round me. ‘We need to get you a thicker jacket.’

‘But now you’ll be cold.’

‘Pah, I’m made of hardier stuff.’

‘Pah?’

‘Yeah, pah!’

I’ve only been here once before, on a flying overnight visit in the summer, to finally meet Calder’s formidable mum Isla. It had been endlessly sunny that day, warm with glorious clear blue skies,...