‘That worked,’ she muttered.
‘It was genius.’ Annabeth squeezed her shoulders. ‘What spell was that?’
‘Loosen,’ Sadie said. ‘I reckoned … well, making things fall apart is usually easier than putting them together.’
As if in agreement, the remaining shell of the building creaked and rumbled.
‘Come on.’ Annabeth took Sadie’s hand. ‘We need to get out of here. These walls –’
The foundations shook. From beneath the rubble came a muffled roar. Shafts of red light shot from gaps in the debris.
‘Oh, please!’ Sadie protested. ‘He’s still alive?’
Annabeth’s heart sank, but she wasn’t surprised. ‘He’s a god. He’s immortal.’
‘Well, then how –?’
Serapis’s hand, still clutching his staff, thrust through the bricks and boards. The monster’s three heads blasted shafts of steam in all directions. Annabeth’s knife remained hilt-deep in the monster’s shell, the scar round it venting red-hot hieroglyphs, Greek letters and English curse words – thousands of years of bad language spilling free.
Like a time line, Annabeth thought.
Suddenly an idea clicked in her mind. ‘Past, present and future. He controls them all.’
‘What?’ Sadie asked.
‘The staff is the key,’ Annabeth said. ‘We have to destroy it.’
‘Yes, but –’
Annabeth sprinted towards the pile of rubble. Her eyes were fixed on the hilt of her dagger, but she was too late.
Serapis’s other arm broke free, then his head, his flower-basket hat crushed and leaking grain. Annabeth’s plywood Frisbee had broken his nose and blackened his eyes, leaving a mask like a raccoon’s.
‘Kill you!’ he bellowed, just as Sadie yelled an encore: ‘Suh-FAH!’
Annabeth beat a hasty retreat, and Serapis screamed, ‘NO!’ as another thirty-storey section of wall collapsed on top of him.
The magic must have been too much for Sadie. She crumpled like a rag doll, and Annabeth caught her just before her head hit the ground. As the remaining sections of wall shuddered and leaned inward, Annabeth scooped up the younger girl and carried her outside.
Somehow she cleared the building before the rest of it collapsed. Annabeth heard the tremendous roar, but she wasn’t sure if it was the devastation behind her or the sound of her own skull splitting from pain and exhaustion.
She staggered on until she reached the subway tracks. She set Sadie down gently in the weeds.
Sadie’s eyes rolled back in her head. She muttered incoherently. Her skin felt so feverish that Annabeth had to fight down a sense of panic. Steam rose from the magician’s sleeves.
Over by the train wreck, the mortals had noticed the new disaster. Emergency vehicles were peeling away, heading for the collapsed apartment building. A news helicopter circled overhead.
Annabeth was tempted to yell for medical help, but, before she could, Sadie inhaled sharply. Her eyelids fluttered.
She spat a chip of concrete out of her mouth, sat up weakly and stared at the column of dust churning into the sky from their little adventure.
‘Right,’ Sadie muttered. ‘What should we destroy next?’
Annabeth sobbed with relief. ‘Thank the gods you’re okay. You were literally steaming.’
‘Hazard of the trade.’ Sadie brushed some dust off her face. ‘Too much magic and I can literally burn up. That’s about as close to self-immolation as I’d like to come today.’
Annabeth nodded. She’d been jealous of all those cool spells Sadie could cast, but now she was glad to be just a demigod. ‘No more magic for you.’
‘Not for a while.’ Sadie grimaced. ‘I don’t suppose Serapis is defeated?’
Annabeth gazed towards the site of the would-be lighthouse. She wanted to think the god was gone, but she knew better. She could still feel his aura disrupting the world, pulling at her soul and draining her energy.
‘We’ve got a few minutes at best,’ she guessed. ‘He’ll work his way free. Then he’ll come after us.’
Sadie groaned. ‘We need reinforcements. Sadly, I don’t have enough energy to open a portal, even if I could find one. Isis isn’t responding to me, either. She knows better than to show up and have her essence absorbed by Lord Cereal Bowl.’ She sighed. ‘I don’t suppose you have any other demigods on speed dial?’
‘If only …’ Annabeth faltered.
She realized her own backpack was still on her shoulder. How had it not slipped off during the fight? And why did it feel so light?
She unslung the pack and opened the top. The architecture books were gone. Instead, nestled at the bottom was a brownie-sized square of ambrosia wrapped in cellophane, and under that …