The first thing that Marine Boy noticed was that his head hurt. The second thing – after he'd forced an eye open for a fraction of a second – was that there was a dazzling white light that seared his retinas like a laser. He closed his eye again, and let out an involuntary moan.

The world swirled around him. First he was floating on a cloud, then he was at the bottom of the ocean's deepest trench, then he was pinned on a slide under a monstrous microscope. He heard, or imagined he heard, disembodied voices.

"Our friend awakes."

"What?"

"I just heard him say something. Well, groan something."

"He still looks out of it to me."

"Oh, he is, more or less. People wake up from that dope real slow – I've seen it before. It'll be a while yet before he can manage a complete sentence, but he's on his way."

"Should we notify anyone?"

"I doubt they'll thank us. They'll want him at least half-conscious before they're dragged down here. But make a note of it in the log, if you like."

Marine Boy tried to force some coherent thoughts past the jack-hammers that had taken up residence in his skull. He was alive, that was the main thing. He'd been drugged by... by... no, he couldn't remember that. He was cold, very cold; and he ached. He had a raging thirst. That was the first priority – something to drink. Had he heard voices? He was almost sure he had. Two voices, possibly, though he'd no idea what they'd been saying. Still, perhaps someone would be able to hear him.

"Water," he said. Or tried to say, anyway. He couldn't tell if he'd actually managed to do so.

He was lying uncomfortably. He tried to work out why. It took a long time, but he eventually realised that he was lying with his full weight on one arm. He tried to pull it out from under himself, but his body didn't seem to be responding properly. On the third try, however, it came free – or, at least, he rolled over onto his back. His arm ached a little less, but he felt that he was now on something colder and harder than previously. He was too exhausted to attempt to move further, however, so he lay still. Somewhere on the edge of his hearing the voices came and went again. He drifted back into oblivion.

Time passed.

Marine Boy had no idea how much time, but found himself once more becoming at least partially aware. He opened one eye again, briefly. The light was still searingly bright. It was not as painful as it had been, but it was still too much for him to cope with. He would have to rely on his other senses for a bit. Feeling first. He was lying on a cold, hard floor. Tile, not stone, which meant that he was indoors, somewhere. Had he been indoors when he'd been... what had actually happened to him? He couldn't remember. Unconnected images flickered dimly in his mind. A submarine, a cave, some ropes... he couldn't work out how they fitted together.

Hearing next. Not much to hear. There was someone – someones – close by and yet a long way away. They spoke to each other in low tones.

Come on, think. He'd been captured, that was plain. He didn't know by whom, but that information would come. Now he had to learn as much as possible about his surroundings, and to remember as much as he could. He wasn't tied up, that was one thing. Not tied up... but he had been tied up, hadn't he? In the back of his mind a memory screamed at him. Tied up... ropes... struggling to free himself... Jack!

Realisation hit him like a slap in the face. Jack. Jack who'd been his friend, but who had tricked him, and betrayed him. The fact that he was a prisoner was unimportant compared to the fact that it had been Jack who'd played him false. Jack, the friend that he'd liked so much, had needed so much. Jack who he'd – yes – loved so much. Had he told Jack that he loved him? He couldn't remember. He rolled onto his side and curled into a ball. And wept, silently.

Time passed.

It took a long while, but eventually Marine Boy found that he was able to think of something other than Jack. Not that he'd pushed the hurt aside, but he'd managed to concentrate on other matters as well. Practical matters. He wasn't tied up. Did that mean that there was a chance of escape? Well, there was always a chance. Perhaps if his captors didn't realise that he was awake, they wouldn't watch him too closely, and he'd be able to make a run for it before they cottoned on. He'd need to have at least some idea where he was first, though. For the third time he forced an eye open. It watered with the pain, but he willed it to stay open. His view was blurred, but he could see that he was in a white-walled room. He was not in a submarine – he would've felt movement, or the vibration of the engines. That meant he was inside that base – the one hidden inside the hill.

He was cold, he ached, he had a raging thirst. Never mind, for the moment. Think. He didn't have his boomerang, or his boots, so no weapons. He wasn't wearing his suit either, or his belt, which meant no oxy-gum. He glanced down at himself, and was relieved to see that he was still wearing his trunks at least. He felt an absurd sense of gratitude towards his captors for allowing him his modesty.

He forced himself to concentrate on practical matters. The odds were long, but he refused to give in to despair. He still had his wits, if he could get them to work properly. He still had his courage. He still had his fists, if needs be – they wouldn't take him down without a fight.

His eye had stopped watering. He blinked a few times to clear it, and opened it a little more. He could see a door. It was closed, and he couldn't guess where it led. Between him and it, however, were some solid-looking iron bars, meaning that he was in some sort of cage. OK, wits were going to be more useful than fists, to start with at least. He looked round the rest of the room. Two bored-looking men were sitting in front of a control panel of some sort, and beyond them was a large opening in the floor. From where he was lying, he couldn't see down into it, but it seemed likely that it was some sort of pool. Possibly that was his way out.

The floor he was lying on was indeed tiled, though there was also a mat next to him. He must've rolled off it, which explained how the floor had got colder and harder. The bars stretched floor to ceiling and the whole width of the room, meaning that he was in a cage some twelve feet by four. There was section of the bars that served as a door, though it didn't tax his wits much to decide that it was certainly going to be locked.

He looked again at the two men. They had the air of being junior technicians, not the sort who made the decisions. He tried to work out whether there was any advantage to be gained from letting them believe that he was still unconscious. He decided that there wasn't – they'd almost certainly been assigned the duty of watching him until he awoke, and then reporting the matter to their superiors. Nothing was going to happen until then; and on the positive side, the men might be persuaded to give him some water.

That was decided, then. Marine Boy sat up slowly. "Where am I?" he asked.