‘Stuck fast,’ Bonhoeffer declared. Martin, too, now saw the adhesive strip with which the bag was affixed to the link of the chain. A good tug would be enough to remove it, but Elena needed to crawl further under the platform.

‘I’m getting a cramp,’ she moaned.

Martin tried to encourage her. ‘You’ll do it. Just a few centimetres more. That’s it, excellent…’

Now the doctor was able to get her whole fist around the bag.

A large wave slapped against the ship, which sounded as if a twenty-metre carpet were being beaten against the hull. The Sultan listed sideways, sending the chain moving a few centimetres as well.

‘This thing can’t go down on its own, can it?’ Elena asked with warranted concern. If the lock was disengaged she’d be yanked along with the chain. ‘I don’t want to end up as anchor grease.’

Bonhoeffer shouted something about her not having to worry, but Elena had already detached the plastic bag and was scrabbling backwards beneath the platform. When she emerged again, the side of her face that had been in contact with the floor had an oily, black trace.

‘It feels slippery,’ the doctor said, standing up.

With her arm outstretched she held the bag as far away from her body as possible, as if she were putting something revolting in the dustbin. ‘Like there’s jelly in it.’

She walked past the anchor winch and over to a green crate where she lay the bag on a hard plastic lid.

‘That may be evidence,’ Martin said. ‘We ought to open it in a sealed container.’

Under an extractor. With safety goggles.

Elena wasn’t listening to him. She might be a good doctor, but she had no idea of the basics of crime scene work. With nimble fingers she tore off the adhesive strip which the bag was tied with before Martin could intervene. Fortunately his fear proved unfounded; there was no combustion. And yet Elena recoiled as if a splinter had flown into her face.

‘Good God!’ she panted, turning away with a hand over her mouth.

Martin could understand her reaction, as well as that of the captain, who stared in disgust at the bag and its contents, which now poured out unimpeded over the lid of the crate. Maggots. Hundreds of them wreathed and coiled as if plugged in to the mains.

‘That’s fucking disgusting!’ Bonhoeffer cursed, stamping on the first of them that had already fallen off the edge to the floor. He grabbed his work mobile and asked someone at the other end to send a cleaner.

Martin moved a little closer and opened the bag to get a better look inside.

Well, well.

The maggots were not the only contents.

With the tips of his fingers he pulled out a laminated, rectangular piece of paper and wiped the insects off it.

‘A postcard?’ the captain asked.

Part of one at least.