The search for the submarine resumed the next day, and this time the crew included Jason. He had left his friends in the town – they had refused to come due to their recent bad experiences involving ships – and though this had been a reluctant decision, they had assured him that they would be fine.

Mac had insisted that Jason come as the latter knew far more about the submarine's final journey than he did. Jason had told him many times that actually, his memories of the incident were somewhat blurred and mostly consisted of trying not to drown, but Mac had said that he might be useful.

So here he was, re-visiting the place that now for him represented not one but two bad memories. It was not a cheerful thought. As he waited for them to reach the spot, a younger sailor recounted to him the events of the previous day – a mostly fruitless search but with the minor excitement when he himself had spotted something on the radar screen.

Jason was naturally curious, but nobody could tell him more. However, their conversation was interrupted by a shout from the other side of the boat.

He couldn't quite hear what Mac was saying but he thought he could distinguish the word flotsam. Therefore he and the young sailor Harry ran round to where Mac was standing, and now holding something that he had probably fished out of the water.

'What did you say your ship was called again?' Mac asked gruffly.

'What? – Oh, the Argo.'

Wordlessly Mac passed him the item in his hands. Jason could not restrain the gasp that leapt up his throat – it was a piece of wood that bore his ship's name clearly, and which had evidently been torn from it by the water or the rocks. He stared at it in disbelief, and at length asked, 'Where... where did this come from?'

'Just found it in the water. Presume it's from your ship?'

Mac's voice was quiet, a little embarrassed perhaps.

'Anyway, we're near the place where you came from... from Atlantis. Seems some of your ship came through too.'

Jason weighed the wood in his hands, remembering his beautiful ship and hardly able to believe that it had run aground, that it had been destroyed by a single careless moment.

'I don't want to believe your story, but I do.'

Jason looked up into Mac's crinkled eyes, unsure of how to respond to this. It was good, of course, that someone believed his crackpot tale – but that didn't change what had happened.

'Don't think we'll find any more of the ship though. We'd better get back to looking for that sub.'

And Mac left Jason, who stood in silent thought, his eyes never leaving the letters carved into the piece of wood: the last remnant, it seemed, of the Argo.

The other four Atlanteans had brought their lunch to the seafront as a bit of a picnic, for it was a beautiful day and they had little else to do; and so they found themselves on a bench, munching on sandwiches with rather obscure fillings (they had made them themselves), watching the waves rolling gently towards the shore, and batting away the hungry gulls that swooped down and threatened to snatch their food from their hands. It should have been perfect, except that they felt entirely out of place and a little lost.

'I hope Jason finds a way back,' said Icarus to fill a lull in the conversation, tossing a piece of bread to an over-eager seagull.

'The chances are very slim,' Pythagoras admitted, 'but not impossible,' he added, seeing his friend's face fall.

'Do you think that people in Atlantis would believe us if we said we'd seen the future?' Icarus asked then.

'Definitely not,' said Hercules, who was already imagining the looks on people's faces when he told them that beer would become less watered down, there would be an abundance of rich food and there would be specific shops for gambling.

'They might do,' countered Pythagoras. 'Stranger things have happened in Atlantis.'

They all had to smile, recalling the numerous escapades in which they had been caught up, several of which had been far more bizarre in many ways than this particular adventure.

'Sorry to spoil the mood,' said a voice behind them, and they all jumped and turned to see Jason, who had just come up from the boatyard: the Scapha had returned.

'What is it?' asked Ariadne, worried.

'We've just found this near to the place where we emerged,' Jason said, handing them the piece of the Argo. All of them studied it in silence; at length Pythagoras spoke.

'So does that mean...'

'That the Argo is probably wrecked, yes,' Jason replied miserably.

'So...'

'If we did manage to find a way back, we would risk being stranded in the middle of the sea with no way back to land,' Jason explained. 'Our chances are looking increasingly unfavourable.'

'But you were washed up on the beach at Atlantis,' said Hercules. 'Weren't you?'

'Yes...' Jason paused. 'There are too many dangers though. I don't want any of you losing your life trying to get back.'

Though they all understood this heartfelt sentiment, Icarus could not help but voice what had occurred to all of them: 'That's a risk I'd be prepared to take.'

'You can't.'

'I can, and I shall.'

'You can't!'

'I can.'

'I won't let you risk your life like that!'

'But, Pythagoras –'

The young mathematician put up his hand to silence Icarus, who stared indignantly at him.

'Icarus,' he said, his voice trembling and betraying the emotions that he was trying to hide, 'It is as Jason said – there are too many dangers. You could drown; you could end up stranded in the middle of nowhere –'

'It's worth the risk,' said Icarus stubbornly.

'Is it? Is it though?'

Pythagoras looked Icarus straight in the eye, placing his hand on his shoulder, trying to calm him.

'I believe it is.'

'I can't let you go.'

'But we would be together.'

Pythagoras shook his head. 'I am afraid that I would not attempt such a thing with such a dismal chance of success. There must be another way.'

'That's what you keep saying. There isn't always another, better way. We would have found it by now.'

Icarus made to turn away, but Pythagoras stopped him, one hand on his shoulder, one hand creeping to the boy's face. Tears ran down his own cheeks; Icarus suddenly felt immensely guilty.

'Stay for me, Icarus, please. Until we find a safer way back. I couldn't bear it if you –'

And then they were both in tears, and found themselves locked in a tight embrace, Pythagoras never wanting to let go, Icarus knowing he couldn't leave without Pythagoras. The situation was a terrible one, and neither of them wished to stay in the future much longer, but they knew in their hearts that it didn't matter where they were as long as they were together.

'That big thing you noticed yesterday...'

Jason posed the question hesitantly, wondering if Mac had dismissed the sighting as unimportant.

'The big thing Harry noticed, you mean?'

'Well, yes. But... I mean, this is going to sound really stupid, but – if there was such thing as a – a time-portal, like in science-fiction, I mean... I mean, if I came through some sort of portal, and you were right above that point... If it was unstable, that might explain why it vanished.'

'Science-fiction is fiction,' Mac said bluntly. 'I expect it was a dolphin or a fish or something.'

'But we must have come through some sort of portal,' Jason said. 'And if it's still there... How did the nameplate of the Argo come through? It hadn't floated far from the point where...'

'Have you been showing your friends Doctor Who or something?'

'Don't you believe me?' cried Jason.

'I did. I do. But I can't. Your friends I can accept exist. The nameplate... that definitely exists. But time-portals? This is getting ridiculous, Jason.'

Mac left the room with the beginnings of a headache and a whirling mind; and Jason sat and thought on this idea, for it had occurred to him suddenly if he could locate the submarine followed by the portal, he might well have found a way back.