Getting out of the sea was now his primary focus. All he had to do was swim to the tender platform that was suspended just above the water line, and climb out.

It wasn’t until he had swum half the length of the ship that he realised the tender platform had gone. Part of the metal staircase that descended from the deck-two hatch was still visible. The rest had apparently come loose and detached itself, along with the platform. Given that it was made from steel, it was, he realised with horror, on its way down to the seabed.

Martin’s limbs were already exhausted from his efforts to escape being crushed. Now it seemed he would have to swim all the way round the cruiser and try to board the Lance, whose hull was much lower and therefore a more realistic prospect for climbing.

He trod water as he considered the Lance. He’d walked all the way round her deck when he had been carrying out his inspection. He couldn’t recall seeing any ropes, ladders, or other means of getting himself up out of the water. Even if he did make it aboard, the walkway was now gone. He’d be out of the sea, but no closer to getting back to the Arcadia’s engine room.

Frustrated, he raised his head to the sky and shouted out in rage.

Which was when he saw the severed umbilical power cord, dangling impotently from the Arcadia. It was ten metres ahead of him, and the end was already in the water.

• • •

In her rush to get to the classrooms, Lucya had overlooked the small matter of the lack of power. On the upper decks it wasn’t so much a problem; daylight flooded in through the windows. The lower she descended, the darker it got.

She continued to be ambushed by questions on every level, slowing her progress. Whilst she tried to remain as polite as possible, her patience began to wear thin. There was confusion and injury on every deck en route, and the more of it she saw, the more worried she became about Erica and the other children. Vardy had been spot on: going to engineering had just been an excuse.

By deck three there was very little light at all. The one upside was that it was possible to pass straight through without being noticed, which meant no stopping to answer the same questions.

Deck two was lit by small portholes. The sun, which had trouble enough penetrating the ever-present thick cloud, didn’t get far into this gloomy area. Most of deck two was the kind of space where the lack of daylight wasn’t a drawback. The sterile conference rooms — now classrooms — the lower level of the cinema, a casino, and crew accommodation. Without power, this warren of corridors and passageways would have been unnavigable for most people. Lucya had been bunked down there for most of her time on the ship, so she could find her way round with her eyes closed. She went directly to the classroom that she had dropped Erica in barely half an hour earlier.

Her first instinct was to peer through the small window in the door. If Miss Linders had everything under control, there was no need to interrupt. The room was, of course, in almost total darkness. Being in the interior of the ship, it benefitted from no natural light at all. However, it looked like someone — Miss Linders, she presumed — had a torch. Its focussed beam was darting around, picking out the faces of children.

The youngsters looked terrified.

“Poor loves,” Lucya whispered under her breath. “Why doesn’t she bring them up to another deck?” She pushed at the door to go and suggest that to the schoolmistress.

The door did not move.

Lucya rattled the handle, but the room had been locked shut. She rapped three times on the glass panel. “Miss Linders? Can you open the door?”

• • •

Martin stood on deck four, hands on his knees, water dripping from his clothes, panting heavily. His head was spinning. The physical exertion had been too much. He wasn’t quite sure how he had managed to climb the electrical and navigation umbilical cord when he was already so drained, but he had. The thick plastic ties that clamped the bundle of cables together at regular intervals had been life savers. Every couple of metres he had rested his feet on them, taking the strain from his arms and hands, getting his breath back before pulling himself ever upwards. As he went, he had thought of Stieg. Martin had been in the water for no more than ten minutes and was already chilled to the bone. He couldn’t imagine how Stieg could possibly have survived more than an hour in such conditions.

Finally he had arrived at deck four, exhausted. It was the lowest deck with an outside area, and so the first opportunity to get back onto the ship. Now he had to get back to the engine room. Just as soon as he got his breath back.

Extra motivation arrived in the form of a crowd of angry passengers. Martin always wore engineering overalls, emblazoned with the Pelagios Line logo. They gave him away as someone who might have answers, and the passengers made that perfectly clear.

“Here, mate. What’s going on with the electric? When’s the power getting switched back on?”

Martin shook his head, showering those closest to him with beads of salty water. “You do realise we’ve just endured some kind of explosion?”

“Yeah? Obviously. And? When’s the electric coming back on?”

“Un-fucking-believable.” Martin glared at the crowd, looking from one person to the next. He pulled himself upright, turned, and walked away, ignoring their protestations and cries.

He arrived in engineering to find Tom Sanderson working with two junior mechanics. They were almost at the point of getting the main diesel electric generator running.

“Ah. Mr Oakley. Hope you don’t mind,” Sanderson began. “Took the liberty of coming down to lend a hand. Didn’t want the lack of electricity to delay the lunch service, you see.”

“Mr Sanderson. How nice to see you.” Martin spoke through gritted teeth. He hated it when Tom poked his nose in, but he was so tired he didn’t really care anymore. In fact, if it meant he could sit down and let someone else do the work, he was quite pleased. “Please, be my guest. I’ll just be over…” He waved a hand in the direction of a desk, and a very inviting chair.

Sanderson nodded and turned back to the others. “So that’s primed, and now we can begin the start-up sequence.”

• • •

There was no answer from Miss Linders, but there were voices. They sounded strange, unfamiliar.

They did not sound like the voices of children.

The beam of light moved frantically, too fast for Lucya to follow. She heard the sound of tables and chairs being dragged around, their sturdy metal legs scraping against the tiled floor. A bang close by made her think something had just struck the door.

Lucya rattled the handle again, then rammed the door with her shoulder. Her instinct told her something was wrong, and that it was important to get in there one way or another.

Then, another noise. A deep, low rumbling. A familiar vibration felt through the soles of her feet. She’d lived with that vibration for years. It had only stopped when they had found the Ambush, and connected to her for power. It was the unmistakable feeling and sound of the Arcadia’s diesel electric generators starting up. One of them, at least.

As the vibration settled down, lights began to flicker into life. The ship’s systems were designed to power up in sequence so as not to draw too big a load from the generators. The first lights to come back on were those far away, down the passage near the cinema. One by one, more sections of illumination were roused, getting closer and closer to Lucya. Then the lights right over her head powered up.

She stopped pushing at the door and tried again to look through the window. With the room beyond still in darkness, all she saw was her own reflection, her eyes wide with fear, although she still didn’t know what she was afraid of.