The first helicopter leaves Dyce at ten to seven. It has left at ten to seven for as long as Morag Leask has been flying, which is long enough that she no longer needs the clock. Her body wakes at five, drinks one coffee, drives the A96 in the dark and walks out to the aircraft at twenty past six. The sea has never once asked her what she's carrying.

In 2009 it was roustabouts and drillers, big men with small bags who slept before the rotors were up to speed. In 2016, the year of the crash in the oil price, it was half as many of them, and nobody slept. In 2027 it was decommissioning crews with cutting gear, flying out to take apart the platforms her father had flown people to when they were new. She remembers that year as the year she started looking at job adverts for flying tourists round the Highlands.

This morning it's eleven passengers. Three technicians with laptops in waterproof cases. Two ROV pilots, both of whom she has flown before, back when they were inspecting pipelines. A crane operator. A woman from an insurance company who is clearly frightened and pretending not to be. And four people from the company that owns the platform now, who talk about "the ring" the way the old crews talked about "the well."

"Same sea," Morag says over the intercom to the insurance woman, who has asked, too brightly, whether it's always this bumpy. "Same weather. It's always this bumpy."

They come in over Skerry Alpha at twenty past eight. From the air it looks almost exactly as it did when it pumped oil. The same yellow cranes, the same scaffold-grey accommodation block, the same helideck with its faded H. The flare stack is gone, and where the process plant used to be there is a long low hall with no windows. Around the platform, in every direction except west, the turbines stand in rows to the horizon, turning steadily in a wind that is, as usual, considerable.

What you can't see from the air is the important part. Sixty metres below the platform, in a ring around its legs, sit the pods.

"Sixty of them," says one of the company people, leaning forward to look down. "Sixty-four by Christmas."

Morag has seen a pod. They brought one up on swap day last spring, while she sat on the deck waiting for a weather window. It looked like the bastard child of a shipping container and a torpedo, painted in anti-fouling red, streaming water and covered in a fine coat of something green. The technicians treated it with a tenderness she found slightly embarrassing to watch.

She sets down, the passengers file off with their waterproof laptops, and the outgoing shift files on. They're tired in the way people are tired after two weeks offshore, and it's the same tiredness she's been flying home for thirty years. Nobody has invented a new kind of tired for data.

On the way back, the oldest of them, a big man with a small bag who was a driller in another life, sits in the front seat and watches the turbines slide by underneath.

"You know what I miss?" he says. "Nothing. I thought I'd miss something. I don't."

"Not the oil?"

"The oil was always going to run out. That's what oil does." He nods at the water. "That lot just keeps blowing."

Morag lands at Dyce at eleven, logs the flight, drinks her second coffee, and goes to look at the rota. It says what it has said for thirty years: two weeks on, three weeks off, ten to seven. Only the cargo has changed.

Next: Haar Compute takes ownership of Skerry Alpha.