Khalid only stopped to buy a paper bag of red, hard-boiled sweets before they set off into the labyrinth of Cairo’s streets. As he led them down shadowy side alleys and onto wide, palm-lined avenues, he popped them into his mouth, one by one. Bast sauntered at his side, her striped tail flicking in the air.

Leah, Mimi, George and William followed behind like ducklings, sticking close so they didn’t lose sight of their guide amongst the bustling crowd. As they wound their way deeper into the city, Leah couldn’t help comparing Cairo to Crickle End. The two were so different! And it wasn’t just the buildings and the people, either. It was the size.

‘This city is huge!’ Mimi whispered to Leah. ‘There’s no way we’ll be able to see it all in a day.’ Leah nodded in agreement. They’d need weeks to explore every inch of it!

But that didn’t mean Khalid wasn’t going to try and squeeze in as much as he could. He showed them the Al-Azhar Mosque, its beige stone walls gleaming pink in the rosy sunlight. They craned their necks to look up at Bab Zuweila, a huge gate in the old city walls, and they trudged on to the Citadel, its domed roofs like little white caps. One of their last stops was the city’s famous Shepheard’s Hotel. It was huge, with potted palms lining the path up to the entrance.

‘Woah, I’ve read about this place!’ George said in awe. ‘It’s really fancy. Loads of important people stayed here.’ He paused, remembering the year. ‘Or they will do, eventually.’

As they followed Khalid away from the hotel, Leah felt Mimi tug her sleeve, pulling her from her thoughts. ‘Hey,’ she said, as George joined them. ‘Have you had any inspiration about why the watch might have brought us back here? Egypt seems like a strange choice after Crickle End.’

Leah bit her lip thoughtfully. ‘I don’t know, but I feel like it might have something to do with him,’ she said, nodding her head towards their guide. Khalid was walking alongside William, deep in discussion about hieroglyphs and codebreaking. Leah couldn’t understand how anyone was able to talk to William for so long, but it seemed like the two of them had connected.

‘Khalid?’ George said in surprise. ‘What makes you think that?’

‘Remember when we arrived in 1921? We ran into Dot almost immediately and it turned out that she was the one we were supposed to help.’ Leah tilted her head to the side. ‘Now, we’ve landed in Cairo—’

‘And met Khalid,’ Mimi finished, nodding her head.

‘I don’t know what he could possibly need help with, though,’ Leah huffed. ‘He seems fine to me.’

‘Let’s stick close to him, just in case,’ George said, and Leah and Mimi nodded in agreement. Besides, Leah thought to herself, even if Khalid wasn’t the reason they were here, he was a very good tour guide.

By the time they came to a halt underneath the shadows of a sprawling palm tree, Leah’s feet were aching from all the walking they’d done. Her neck itched, too, and she hoped she hadn’t got a sunburn.

‘Ugh,’ Mimi said, pushing her braids back over her shoulder and wiping a hand across her forehead. ‘I’m so sweaty!’

‘That was so cool, Khalid!’ George cried enthusiastically. ‘Cairo is amazing!’

William rolled his eyes. ‘Get a life, George. There’s nothing special about a bunch of old buildings. Hieroglyphs on the other hand . . .’ He exchanged a grin with Khalid.

‘I’m glad you enjoyed my tour! Although, of course, no trip to Cairo is complete without a cruise on the Nile!’ Khalid smiled mischievously. ‘If we hurry we might be in time . . .’

‘In time for what?’

‘Amma’s mentor, Professor Gladstone, owns a steamer and I heard him telling her that he was planning to take some of his friends out on the river this afternoon. If you like, we could see if he’d let us come along, too?’

‘Wow! That would be amazing!’ George turned to the others, his face bright with excitement. ‘The Nile! It’s one of the most important rivers ever! It’s been one of the busiest transport systems since ancient times.’

William rolled his eyes.

‘Won’t Professor Gladstone mind?’ Leah asked.

Khalid shook his head. ‘Not at all! The professor is a very nice man. I’m sure he’d be eager to show Cairo off to more visitors.’

‘Come on, L!’ George said. ‘We can’t miss a chance like this!’

Leah had never seen her friend so excited. ‘Okay.’ She grinned. ‘Let’s do it!’

They weren’t far from the banks of the Nile, so it was only a short walk down to the water. Khalid led them to a small wooden jetty. Tied up at the end was Professor Gladstone’s steamer. On its white-painted hull was the name PS Cleopatra. The children slowed to admire it.

Leah hadn’t been on many boats, and none that were as impressive as this one. It was huge, with a two-storey deck balanced in the middle like a tiered wedding cake. A huge chimney burst out of the top, and at the back, a giant paddlewheel was semi-submerged in the blue-green Nile waters.

‘What does the “PS” stand for?’ Mimi asked. ‘It’s not like the bit you put at the end of a letter, is it?’

Khalid laughed. ‘No, it stands for “paddle steamer”. See that big wheel at the back? That’s the paddlewheel. There’s an engine inside the boat that produces steam and then the steam makes the wheel turn, pushing the boat through the water.’

‘Do many people own boats like this?’ Leah said, taking it all in.

Khalid shook his head. ‘Oh, no. Only the richest.’ He leaned forward. ‘You know, I heard Amma Amina say once that Professor Gladstone is distantly related to the British royal family.’

‘What’s he doing out here then?’ William asked rudely. ‘Royalty live in palaces, not sweaty, smelly cities.’

‘William!’ Mimi exclaimed.

‘It’s okay,’ Khalid said with a slight smile. ‘Cairo can take some getting used to. To answer your question, though, Professor Gladstone is an academic. He’s come all the way from Cambridge University to learn about the Ancient Egyptians.’

‘That’s cool!’ George jumped in enthusiastically. ‘I love Egyptian history, I—’

Before George could say any more, two figures disembarked from the boat and began to walk along the jetty towards them. It was Amina and Professor Gladstone.

‘Come on,’ Khalid said, beckoning them forward. He stooped and gathered Bast up in his arms, leading them towards the PS Cleopatra.

‘Khalid!’ Amina’s voice was sharp. ‘Where have you been?’

‘I was making new friends, Amma,’ Khalid said, and Amina’s gaze flicked over his shoulder to where Leah, Mimi, George and William were waiting. Her eyes lit with recognition.

But it was the professor who spoke first. ‘Ah, yes! Our hasty acquaintances from this morning. What a surprise!’

‘They’ve only just arrived in Cairo, Professor,’ Khalid said. ‘I was giving them a tour of the city. But we didn’t get a chance to see the Nile. I was wondering . . .’ He trailed off. For the first time since they’d met him, Khalid looked a little unsure.

‘If they could come on our river cruise?’ the professor finished. His eyes twinkled with amusement.

‘Khalid,’ Amina sighed. ‘You can’t just invite people aboard a boat that doesn’t belong to you.’

But the professor only laughed, placing a hand on Amina’s shoulder. ‘It’s perfectly fine, Amina. After all, as I’ve told you many times, what belongs to my family belongs to yours!’ He turned towards the children. ‘I’d be delighted to have such brave explorers accompany me down the Nile river. It would be smashing to show the younger generation the wonders of Egyptian history! Come along, now. We’re set to depart soon.’

Professor Gladstone led them down the creaking jetty, directing them up a small ramp onto the Cleopatra’s lower deck. Leah breathed a sigh of relief as she stepped into the shade. She was grateful to get out of the fierce Egyptian sun.

Professor Gladstone clapped his hands together as he joined them on board. ‘Right, I believe it’s almost time for lunch. Oh . . .’ he trailed off, frowning at the children from beneath bushy grey eyebrows. It was like he’d only just seen them properly. ‘What on earth are you all wearing?’

Leah and the others looked at each other and then down at themselves. In the excitement of meeting Khalid and exploring the city, she’d completely forgotten that they were still wearing their now very dirty and sweaty school uniforms.

‘Er . . .’ Leah stammered, desperately looking for an excuse.

‘We were playing dress up!’ Mimi suddenly burst out. ‘We brought them with us from back home and we thought it would be fun to wear them around the city.’

Leah held her breath as Professor Gladstone and Amina exchanged a look. But then the professor burst out laughing. Even Amina gave a small smile.

‘Not to worry,’ Gladstone said, smiling. ‘I keep some spare clothes on the boat for when my grandchildren come to visit. I’m sure there’ll be something for each of you to change into. You’ll all be much cooler.’ He beckoned to a man that looked like a butler and began giving him instructions to escort the children upstairs.

‘Gladstone!’ a deep voice suddenly called out, and Leah turned to see a group of white men trooping down the deck towards them. They were of varying ages, but all of them wore pale, linen suits and matching hats similar to the professor’s. The one in front was short and round, with a pair of wire spectacles balanced on his upturned nose. His eyes swept over the children and then away as if he’d already decided they weren’t important enough for his attention.

‘Travers, so good to see you, old sport!’ Gladstone answered, striding towards the man with his hand outstretched.

‘Come, children,’ Gladstone’s butler said, beckoning Leah, Mimi, George and William towards a set of stairs leading to the upper deck.

‘I’ll wait for you down here,’ Khalid whispered.

As Leah followed the others towards the stairs, she couldn’t help but look back over her shoulder at Professor Gladstone and his visitors.

‘Let me introduce you to my student,’ he said. He waved at Amina, who had been standing awkwardly off to the side. ‘This is Amina Hossam. She’s one of the most talented Egyptologists I’ve ever met. She sees things that most people miss.’

Travers gave a bark of loud laughter as he eyed Amina, his expression amused. ‘Her? Goodness, Gladstone, how extraordinary. A woman? An odd choice to carry the little that remains of your legacy.’ He sniggered. His voice reminded Leah of William’s when he was being particularly unkind. For a moment, no one said anything. Amina’s eyes were fixed on the floor and the professor’s face was frozen in a strained grimace.

‘L!’ Mimi’s voice made Leah jump and she whirled around. Her friends were all standing on the stairs, waiting for her. ‘Come on!’

With one final glance over her shoulder, Leah hurried to catch up with the others.