For the third morning in a row, Kensy was awake well before dawn. She surveyed the room, where everyone else was still fast asleep. Harper let out a little grunt and rolled over, but within seconds her breathing was deep and even. Kensy peered over the edge of the bunk at Autumn. She didn’t want to wake the girl, but she needed to go for a run to clear her head. She had dreamt about her parents last night and, while she couldn’t remember the details, it had left her feeling as if a cage full of guinea pigs was gnawing away at her stomach lining.

Kensy slipped silently from the top bunk, grabbed her tracksuit and trainers and tiptoed into the bathroom. She scribbled a note and placed it on her pillow in case anyone woke up and wondered where she’d gone. The girl then tiptoed to the door, opening and closing it with the gentlest of clicks. She was feeling quite proud of herself when a clock chimed, sending her skywards. As if it wasn’t bad enough having a zillion noisy timepieces inside the house, there was a huge grandfather clock in the hallway of the stables too. It had just gone six. Kensy reached the main door and was surprised to see her brother emerge via the sitting room. He was also dressed and had a torch in his hand.

‘What are you doing?’ he whispered. Kensy wasn’t usually up at this hour.

‘Going for a run,’ she whispered back. ‘I couldn’t sleep.’

‘Me too,’ he said. ‘Fancy some company?’

Kensy nodded. She was glad of the chance to talk with him, away from everyone else.

The twins exited through the main stable door, the cold winter air chilling their noses and cheeks as they made their way towards the walled garden and around to the back of the building. The moon cast an eerie glow.

‘Where do you want to go?’ Max asked.

‘Anywhere,’ Kensy said, breaking into a jog.

The pair soon fell into a rhythm, their footsteps crunching on the gravel path. They ran past the maze and through an open field towards the jagged cliffs. There was a path that hugged the coastline. A way off in the distance, perched on the most easterly point, was a lighthouse. Every fifteen seconds, a beam of light illuminated the inky sea.

‘Do you want to run out there?’ Kensy suggested, barely panting.

‘Better not,’ Max said. ‘It’s a long way, and we have to be back in time for breakfast. Let’s look at that place instead.’ He flashed his torch across the field, the beam connecting with a building he’d noticed yesterday when they were training.

They diverted off the trail and ran side by side in silence, their pace quickening. Somewhere in the distance they could hear the clattering of an engine and saw the flickering of headlights, but were too far away to get a proper look at the vehicle. Seconds later, it was gone.

‘Do you sometimes feel like we went to sleep on our last night in Australia and we still haven’t woken up yet and all of this is some kind of crazy dream?’ Kensy said.

‘Every day,’ Max replied. ‘But then I remember it’s real and this is our life and we’d better get used to it. Even if . . .’ He paused and swallowed his words. ‘Even when Mum and Dad come back, I can’t imagine we’ll just up and leave. Can you?’

Kensy stopped, her chest heaving. She shook her head, struggling to catch her breath. ‘I don’t want to.’

Max halted a few paces ahead and turned to face her. He was surprised to see his sister was close to tears.

‘We’ve only just met Granny and Mim and Song and everyone else. I don’t want to lose them,’ she said.

‘Me neither.’ Max shook his head. ‘And we don’t really know Uncle Rupert at all. He intrigues me.’

Kensy grinned, brushing at her eyes with the back of her hand. ‘Intrigues or annoys?’

‘Not sure yet,’ Max said. ‘Come on, I’ll race you to the wall over there.’

‘Okay, but prepare to lose, little brother.’ Kensy began to count down from five but sprinted on two.

‘Hey!’ Max shouted, and sped after her.

The twins galloped across the field, reaching the wall that encircled the building at almost exactly the same time.

‘You cheated,’ Max panted, his breaths punctuating the still air.

Kensy scoffed. ‘I just gave myself a head start, that’s all.’

Even in the pre-dawn light, the children could see that it was an impressive structure with a domed roof and Doric columns. They jogged around the wall until they found a set of steps.

‘What do you think it is?’ Kensy asked, bounding up two flights.

‘Maybe it’s a chapel or something,’ Max said, ever the pragmatist.

‘Or the world’s fanciest garden shed, more like. Hey, there’s a door!’ Kensy raced towards it. Finding it locked, Kensy reached up and pulled out her new hairclip. She’d forgotten to wear it yesterday and had been in big trouble with Mrs Vanden Boom.

Max wandered around the terrace, trying to find another way in, but seconds later, Kensy pushed the door open.

‘Are you coming or not?’ she called.

Max ran back to join his sister. ‘That was quick even for you.’

‘It helps when you have the Swiss Army knife of hairclips,’ she replied, returning it to the maelstrom of her unruly locks.

Max’s eyebrows jumped up. He was still getting used to the amazing gadgets available to them since joining Pharos and thought the girls’ hairclips, with their array of tools and weapons, were spectacular. He almost wished he could wear one too.

They walked inside and Max flashed his torch about. There were carved niches in the walls with polished brass plaques above.

Kensy frowned. ‘What is this place?’

‘I believe it’s a guesthouse of sorts,’ Max replied, smiling to himself.

‘But there’s nothing in here – where are the beds?’ Kensy took the torch and pointed it at one of the inscriptions. Their grandfather’s name was written on it and there was a short spiel about him underneath.

Kensy’s eyes widened when she realised that this was the type of guesthouse where everyone was staying permanently. ‘Um, I think we’re in the family crypt.’

‘Uh-huh.’

‘But where are they?’ Kensy whispered, as if she might wake someone up.

‘I’d say they’re down below – or in the walls. There was another level, remember? We had to come up two flights of steps to get here.’

Kensy shuddered. ‘Eww, gross. Let’s go.’

‘Throw me the torch,’ Max said.

Kensy tossed it as she reached the door.

Max read several more plaques before something on the floor caught his attention. In the centre of the marble surface was a perfect circle and within it were the numbers zero to one hundred and forty-four. It was jibberish to most people, but not to Max. He mumbled the numbers and some variations then stepped on them in an order that seemed to make sense. First zero then one, one again, two, three, five, eight, thirteen, twenty-one, thirty-four, fifty-five, eighty-nine and, finally, one hundred and forty-four.

‘Come on, Max,’ Kensy hissed from the doorway. ‘This place gives me the creeps. It’s full of dea–’

There was a loud grating sound as the marble slab slid away to reveal a spiral staircase rising up from the floor. Without a backwards glance, Max disappeared. Kensy was at a loss for words. This wasn’t like her brother at all. He was always the careful one – she practically had to drag him along on any adventure. Not to be outdone, Kensy scampered after him. ‘If we come across one skeleton, I will never forgive you,’ she called, her threat bouncing around the walls.

Max was just about to step off the last tread when he halted and hung back. Kensy crashed into him, sending her brother flying forward. He gripped the banister and spun around, pulling himself back onto the step before his feet could touch the ground below.

‘Why did you stop?’ Kensy demanded.

‘Because I think I might have ended up like that guy.’ Max exhaled and shone the torch onto the marble floor. There, in front of them, was a mouse that had been sliced right through the middle.

Kensy gasped. ‘Oh.’

Max fished around in his hoodie pocket and pulled out a chocolate bar he’d squirrelled away the day before. He threw it onto the floor and waited but nothing happened. Maybe he was wrong. He leaned forward just as a chequerboard of razor-sharp guillotines thrust upwards, cutting the chocolate bar clean in half.

‘Whoa,’ Kensy breathed. ‘That could have been us. Whatever’s down here must be important.’

Max could feel his heart thumping in his chest.

‘There’s got to be a way to turn it off,’ Kensy reasoned.

Max felt under the metal railing of the banister and bobbed down to take a closer look. There was a small switch. He pushed it and the steel blades retracted.

‘Are you sure it’s safe?’ Kensy asked.

‘There’s only one way to find out.’ Max leapt off the last step and into the circular room.

It was much bigger than the level upstairs. A bench ran all the way round and above, and below it were literally hundreds of drawers, each bearing a number.

Max opened a drawer marked ‘1967’, hoping it wasn’t booby trapped. It was crammed full of papers. He lifted one out and found it was a front page from the Beacon, but, rifling through, there were other newspapers too. The first headline read ‘74 dead in Russian Train Derailment’. He pulled out another: ‘Australian Prime Minister Lost Off Cheviot Beach.’

‘That’s a bit careless,’ Max mumbled to himself.

‘It’s an archive,’ Kensy called from the other side of the room. ‘Like the one in the tower except that was mostly all about us.’ When she and Max had first arrived at Alexandria, they had discovered the tower and its contents but hadn’t realised it was where their grand mother kept all of their cast-off clothes and copies of their school awards and reports and such.

‘Yes,’ Max agreed. ‘The number on the drawer is the year. But I’ve only found front pages over here. Not just from the Beacon either. There are lots of different papers.’

Kensy had discovered the same thing. Coincidentally, she was searching through the year she and Max were born. There was a headline about an avalanche in France and another about an oil spill off the coast of Alaska, but it was the third one she read that caused the girl to check herself. ‘Max, come here,’ she shouted. ‘Now!’

He quickly returned the papers to the drawer and hurried to his sister. She was holding a page from the Times. Emblazoned in large letters were the words ‘Newspaper Heir Killed in Plane Crash’.

Max scanned the text. According to the story, his parents and Fitz had perished in a plane crash in the Andes. They were on holiday in Peru and their father was flying the private jet when the plane disappeared in mountainous terrain. Wreckage had been spotted and, once they could access it, bodies were likely to be recovered. Max read to the end of the report, then looked up. ‘Did you see this bit?’ he said, pointing at the page. ‘Sadly, Anna Spencer’s own parents, prominent medical scientists, Hector and Marisol Clement, were murdered in a botched robbery last spring in their Paris home. A representative for Dame Cordelia Spencer has asked that the media respect the family’s privacy at this terrible time.’

Kensy’s eyes widened. ‘Our grandparents were murdered? Mum never mentioned that. Come to think of it, she’s never really told us much about them.’

‘How do we even know it’s true?’ Max said. ‘After all, Mum and Dad and Fitz didn’t die in a plane crash.’ He glanced at his watch. ‘We’ve got to go,’ he said, and returned the page to the drawer. ‘We’re going to have to sprint back. If we’re late, Vanden Boom will be having us for breakfast!’

The children made sure that nothing was out of place, then ran up the stairs. Max paused at the top, wondering how to reset the whole thing. As if sensing there was no one inside, the staircase retracted and the stone rumbled back into place of its own accord. Problem solved.