“Because if you did, I’d fall in the water,” says Violet. “And if that happened, you’d lose this.” And she pulls something out of her pocket, and holds it up.

It’s the big pebble of ruby-red sea glass that Mrs Fossil found, and which the doc used to lure the malamander to the museum – the pebble of sea glass that Violet took from Dr Thalassi’s dressing-gown pocket.

Violet is holding the torch in the same hand, in such a way that the light shines through the glass pebble, making it glow a deep and magical red.

“But…” Eels’ mouth drops open. His hands and the harpoon gun fall to his side as he splutters his astonishment. “But … how? How can you have the egg already?”

Then a look of dark fury passes over his eyes and the harpoon gun snaps back up. But before he can fire, Violet flings the glass pebble far out over the flooded cavern.

It lands in the water …

ploop!

… and vanishes from sight.

“The tide’s already rising,” she shouts. “You’ll never find it in time.”

“No!”

Eels scrabbles to get his mouthpiece in and the goggles over his eyes. He snaps the head-mounted torches on as he runs back down the slimy mound and dives into the water.

And he’s gone.

“OK, Vi,” I say, giving a slightly desperate laugh of relief. “Nice trick. Now we need to get out of here.”

“Not yet, Herbie.”

And Violet makes her way along the iron girder, and then jumps across to a buckled section of wall that is still above water. She runs across it smartly and jumps onto the mound.

“Vi!” I shout, running to the end of the girder, waving my wristwatch in the air. “There’s no time! We have to get out of here!”

“I can’t go yet, Herbie,” she calls back to me. And she climbs up the seaweed nest, towards the egg.

Cursing and gasping, I jump after her. I fall flat on the stinking mound, face first, and then start to crawl upwards through the bones and filth. By now I’m ready to drag Violet out of the ship if I have to. But when I get to the summit, I see her crouching over the softly glowing egg, reaching her hands gingerly forward like she’s afraid to actually touch it.

“What are you doing?” I want to say, but the words won’t come.

The egg is astonishingly beautiful.

It’s like a promise of all things wonderful.

It’s like a crystallized dream.

Then Violet touches it and it blazes, casting an eerie, dancing light over her wondering face.

“The malamander egg,” says Violet, to herself not to me. “It’s the malamander egg.”

I shake my head clear. I look around. The water is definitely higher than it was before. “Vi, we’re leaving. Now!”