‘Give us a call when you’re finished. Good luck,’ he offered.

Rhona listened to Erling’s retreating steps. Eventually silence fell except for the continuing creaks and groans of metal on metal, plus the constant drip of water from somewhere close at hand.

The cell, she estimated, was roughly six foot by six, the height a little more than that. She took a series of photographs from the low doorway, then, stepping inside, took a full 360-degree video.

There was a bed of sorts along the back wall, a little pile of clothing on the right-hand side. On the left was the food and rubbish area. A stack of unopened tins of beans, tuna, corned beef; a plastic bag with the empties. A cutlery set was there, but no plate or bowl. It looked as though whoever had hidden here had been eating straight out of the tin. There was also a stack of water bottles, one partially drunk.

Before lifting DNA samples, she checked the clothing. Jeans, tops, jumpers and some underwear which all suggested the stowaway had been female.

Erling had exhibited some unease at Rory’s announcement of that the previous evening. Most likely because she hadn’t yet examined the hideout and its contents.

However, if a girl had made it to shore from the Orlova, the best way to find her would be to alert the local population to her existence. And the sooner the better.

As she worked, Rhona was conscious that the Orlova was never still or silent, but constantly ringing with sound as it strained against its anchor. The noises, of course, were never of human life. It was as though the ghost ship had swallowed everyone, including whoever had taken refuge here in this hidden room.

Two hours later, she had collected her evidence. Long strands of human hair, dark blonde in colour, DNA saliva and blood samples and, interestingly, some short animal hairs, both white and black.

The thought had crossed her mind that the room may have been used in one of the many games played on board, so the animal hairs might relate to costumes similar to the Viking outfits, the blood spots to minor injuries sustained. Then again, from experience, when viewed via her magnifying glass, she thought the hairs had possibly come from a dog, although she would have to confirm this under the microscope back in the lab.

Shortly after she’d bagged everything, Erling reappeared.

‘It’s getting a bit wild out there, so we’d like to get you off and safely back to Houton.’

‘What about Glasgow?’

‘The helicopter won’t go now. You’re here for another night, I’m afraid.’

Making their way up on deck, Rhona was surprised at the increased pitching of the Orlova, something she’d missed during her time in the cell. The wind having risen, its gusts now threatened to take the feet from under her, until Erling grabbed a hold.