Life with Mac was chaotic at the best of times. His various jobs at sea, and Jason's part-time work in the town, brought in just enough money for the two of them to live reasonably in their little house by the sea. Now, suddenly, there were four extra mouths to feed, four extra people to house somehow in a cottage that barely held two. This issue was the first brought up at the dinner-table that night, for Mac was practical above all else, and despite his disbelief in Jason's story, he accepted that the four strangers were real.

'You're telling me this woman's your wife?' he asked, pointing to Ariadne with a plastic knife whilst stabbing vaguely at his takeaway with a plastic fork. He had bought them each a portion of fish and chips – "can't go wrong with fish and chips", he had said, which had proved a foolish opinion, for the people of Atlantis had never eaten such food before and did not particularly like it.

Jason nodded shyly, his hand finding Ariadne's under the table.

'Well, I suppose she'll have to stay then.'

'What about the others?' asked Jason quickly, not wanting Mac to dismiss his friends and force them to make their own way in a world that wasn't their own.

'Well...' Mac's gaze went from the slightly scared face of Pythagoras to the defiant face of Icarus, to the somewhat resigned face of Hercules, who was scoffing his food with rapidity, if not enjoyment.

'They can stay for a bit,' he said at last. 'But they can't live here forever. Much as I would like to help your friends, Jason – we simply can't afford it.'

'Pythagoras?'

'Mm?'

'Can you not sleep either?'

'Not really.'

There was a rustling of bedcovers as Icarus turned over, trying to see Pythagoras. Though the night was lighter than those he was used to – there was some sort of light just outside that was getting on his nerves rather – he wasn't sure he liked sleeping in the creaky old cottage in the dark.

'What do you think will happen to us?'

'I don't know, Icarus.'

'Will I ever see my father again?'

Icarus's voice cracked. The situation had only just dawned on him – it had just occurred to him that never getting back to Atlantis was a very real possibility.

'If Jason got to Atlantis from here, then there must be a way.'

'Mm...'

Pythagoras found what he thought was Icarus's nose and kissed it lightly. 'We should try to get some sleep. Pretend we are still in Atlantis.'

'If only,' muttered Icarus, rolling over and closing his eyes.

'It's simple really.'

Jason was bumbling about the kitchen, setting out bowls, and then plates when he ran out of bowls; then he set a box of cornflakes on the table before going to the fridge for the milk. Pythagoras, Icarus and Ariadne had all turned up for breakfast; Hercules was still snoring loudly in the next room. Mac was also absent, as he set off early for the boatyard every morning and was rarely at home.

'What's simple?' asked Icarus.

Seeing that none of his friends had made a move towards the cornflakes, Jason poured some out for each of them. 'You can put milk on them if you like. I think they taste better – they're a bit dry without – I mean, Mac eats them dry, but that's because he doesn't want to run out of milk.' For the first time in his life he found himself terribly embarrassed for living in such a poor household. He knew now what Pythagoras must have felt like when he moved in after arriving in Atlantis.

'Well, when I ended up in Atlantis, it was because I had gone under the sea in a submarine, and then something happened – I think I almost drowned – and then – and then I was in Atlantis.'

Jason had briefly mentioned this in his account of his adventures the previous day, but it still sounded fairly incredible to the others.

'Anyway, we got back here in pretty much the same way, so if we want to get back...'

Pythagoras almost choked on his breakfast. 'You mean we should try to almost drown and then we might get back?'

'It's a bit risky...' Jason sighed. 'Okay, so it's a bit insane, but it's our only chance.'

'And if it doesn't work?' Ariadne, who had been silent until that point, now stared at Jason with wide and rather fearful eyes.

'Well... we drown.'

'That does not sound favourable,' Pythagoras muttered, munching on his cornflakes, which were at a perfect state of milkiness due to his proficiency at pouring things at precisely the right angle.

'What doesn't sound favourable?' Hercules stumbled into the kitchen, bleary-eyed. He sat at the table; Jason pushed a plate piled with cornflakes towards him.

'Drowning,' said Pythagoras with a weak smile.

'No, not really.' Hercules nibbled at a cornflake. 'Have you got any more of those... biscuit things from yesterday?'

'You don't eat biscuits for breakfast,' Jason said.

'Well, I don't usually eat dried leaves either,' said Hercules. Jason couldn't tell if he was joking or not, but decided not to ask.

'What do you want to do today?' Jason asked at length.

'Can you show me the theorem that you mentioned yesterday?' asked Pythagoras, looking eager for the first time since arriving in the future.

Jason couldn't help laughing. 'Yes, okay, there's a library in town, I'll show you.'

'A library!' Pythagoras's eyes lit up.

'We'll go to the library first,' Jason decided. He loaded up the dishwasher and set it going, and then smiled. 'Let's go then.'

It wasn't a big library, but it was a pleasant and cosy one, and surprisingly well-stocked. Pythagoras and the others were however surprised to find it filled not with scrolls but with books. Jason explained briefly that books were simply collections of scrolls, and Pythagoras seemed quite pleased with this particular technological progression, scurrying to the reference section and burying himself in the first book he came to, which happened to be a travel guide to Australia, and which he found singularly fascinating, despite never having known that the country, or even continent in which it was located, existed.

He was busy scrutinising the map in the back cover when Jason came over, casting his shadow over the page with another book that he had opened for Pythagoras's inspection. Pythagoras set down his book carefully and received the one Jason was proffering, which was about geometry.

The young mathematician's eyes quickly fell on the words Jason had meant him to see: "Pythagoras's theorem". A sharp gasp escaped him, and he stared, stunned, at the page, looking at it without seeing it. Eventually his eyes focused enough for him to inspect the accompanying diagram.

'But that's the theorem...'

'...that you were first to prove, I know,' Jason replied with a chuckle. 'They named it after you.'

'But... but...' Pythagoras stammered, his cheeks burning but a shy smile beginning to spread across his face. All of a sudden he felt a lump in his throat. 'But that means...'

'...that you're probably one of the most famous people from the ancient world,' finished Jason, still laughing at his friend's astonished impression and feeling his heart leap.

'But I just proved it, I didn't...'

'Try explaining that to centuries of teachers and schoolchildren.' Jason put his arm around his friend's shoulder as tears sprang to Pythagoras's eyes. 'Have a look at the other maths books if you like; I'm going to find Hercules a book about Greek mythology...'