'If we do push the b.u.t.ton for twelve minutes,' Percy said, 'and the chains are cut '

'The Doors should reset,' Bob said. 'That is what they are supposed to do. They will disappear from Tartarus. They will appear somewhere else, where Gaia cannot use them.'

'Thanatos can reclaim them,' Annabeth said. 'Death goes back to normal, and the monsters lose their shortcut to the mortal world.'

Percy exhaled. 'Easy-peasy. Except for ... well, everything.'

Small Bob purred.

'I will push the b.u.t.ton,' Bob volunteered.

A mix of feelings churned in Percy's gut grief, sadness, grat.i.tude and guilt thickening into emotional cement. 'Bob, we can't ask you to do that. You want to go through the Doors, too. You want to see the sky again and the stars and '

'I would like that,' Bob agreed. 'But someone must push the b.u.t.ton. And once the chains are cut ... my brethren will fight to stop your pa.s.sage. They will not want the Doors to disappear.'

Percy gazed at the endless horde of monsters. Even if he let Bob make this sacrifice, how could one t.i.tan defend himself against so many for twelve minutes, all the while keeping his finger on a b.u.t.ton?

The cement settled in Percy's stomach. He had always suspected how this would end. He would have to stay behind. While Bob fended off the army, Percy would hold the elevator b.u.t.ton and make sure Annabeth got to safety.

Somehow, he had to convince her to go without him. As long as she was safe and the Doors disappeared, he could die knowing he'd done something right.

'Percy ...?' Annabeth stared at him, a suspicious edge to her voice.

She was too smart. If he met her eyes, she would see exactly what he was thinking.

'First things first,' he said. 'Let's cut those chains.'

LXIV.

PERCY.

'IAPETUS!' HYPERION BELLOWED. 'Well, well. I thought you were hiding under a cleaning bucket somewhere.'

Bob lumbered forward, scowling. 'I was not hiding.'

Percy crept towards the right side of the Doors. Annabeth sneaked towards the left. The t.i.tans gave no sign of noticing them, but Percy took no chances. He kept Riptide in pen form. He crouched low, stepping as quietly as possible. The lesser monsters kept a respectful distance from the t.i.tans, so there was enough empty s.p.a.ce to manoeuvre around the Doors, but Percy was keenly aware of the snarling mob at his back.

Annabeth had decided to take the side Hyperion was guarding, on the theory that Hyperion was more likely to sense Percy. After all, Percy was the last one to have killed him in the mortal world. That was fine with Percy. After being in Tartarus for so long, he could barely look at Hyperion's burning golden armour without getting spots in his eyes.

On Percy's side of the Doors, Krios stood dark and silent, his ram-horned helmet covering his face. He kept one foot planted on the chain's anchor and his thumb on the UP b.u.t.ton.

Bob faced his brethren. He planted his spear and tried to look as fierce as possible with a kitten on his shoulder. 'Hyperion and Krios. I remember you both.'

'Do you, Iapetus?' The golden t.i.tan laughed, glancing at Krios to share the joke. 'Well, that's good to know! I heard Percy Jackson turned you into a brainwashed scullery maid. What did he rename you ... Betty?'

'Bob,' snarled Bob.

'Well, it's about time you showed up, Bob. Krios and I have been stuck here for weeks '

'Hours,' Krios corrected, his voice a deep rumble inside his helmet.

'Whatever!' Hyperion said. 'It's boring work, guarding these doors, shuffling monsters through at Gaia's orders. Krios, what's our next group, anyway?'

'Double Red,' said Krios.

Hyperion sighed. The flames glowed hotter across his shoulders. 'Double Red. Why do we go from A-22 to Double Red? What kind of system is that?' He glared at Bob. 'This is no job for me the Lord of Light! t.i.tan of the East! Master of Dawn! Why am I forced to wait in the darkness while the giants go into battle and get all the glory? Now, Krios I can understand '

'I get all the worst a.s.signments,' Krios muttered, his thumb still on the b.u.t.ton.

'But me?' Hyperion said. 'Ridiculous! This should be your job, Iapetus. Here, take my place for a while.'

Bob stared at the Doors, but his gaze was distant lost in the past. 'The four of us held down our father, Ouranos,' he remembered. 'Koios and me and the two of you. Kronos promised us mastery of the four corners of the earth for helping with the murder.'

'Indeed,' Hyperion said. 'And I was happy to do it! I would've wielded the scythe myself if I'd had the chance! But you, Bob ... you were always conflicted about that killing, weren't you? The soft t.i.tan of the West, soft as the sunset! Why our parents named you the Piercer, I will never know. More like the Whimper.'

Percy reached the anchor hook. He uncapped his pen and Riptide grew to full length. Krios didn't react. His attention was firmly fixed on Bob, who had just levelled the point of his spear at Hyperion's chest.

'I can still pierce,' Bob said, his voice low and even. 'You brag too much, Hyperion. You are bright and fiery, but Percy Jackson defeated you anyway. I hear you became a nice tree in Central Park.'

Hyperion's eyes smouldered. 'Careful, brother.'

'At least a janitor's work is honest,' Bob said. 'I clean up after others. I leave the palace better than I found it. But you ... you do not care what messes you make. You followed Kronos blindly. Now you take orders from Gaia.'

'She is our mother!' Hyperion bellowed.

'She did not wake for our war on Olympus,' Bob recalled. 'She favours her second brood, the giants.'

Krios grunted. 'That's true enough. The children of the pit.'

'Both of you hold your tongues!' Hyperion's voice was tinged with fear. 'You never know when he is listening.'

The elevator dinged. All three t.i.tans jumped.

Had it been twelve minutes? Percy had lost track of time. Krios took his finger off the b.u.t.ton and called out, 'Double Red! Where is Double Red?'

Hordes of monsters stirred and jostled one another, but none of them came forward.

Krios heaved a sigh. 'I told them to hang on to their tickets. Double Red! You'll lose your place in the queue!'

Annabeth was in position, right behind Hyperion. She raised her drakon-bone sword over the base of the chains. In the fiery light of the t.i.tan's armour, her Death Mist disguise made her look like a burning ghoul.

She held up three fingers, ready to count down. They had to cut the chains before the next group tried to take the elevator, but they also had to make sure the t.i.tans were as distracted as possible.

Hyperion muttered a curse. 'Just wonderful. This will completely mess up our schedule.' He sneered at Bob. 'Make your choice, brother. Fight us or help us. I don't have time for your lectures.'

Bob glanced at Annabeth and Percy. Percy thought he might start a fight, but instead he raised the point of his spear. 'Very well. I will take guard duty. Which of you wants a break first?'

'Me, of course,' Hyperion said.

'Me!' Krios snapped. 'I've been holding that b.u.t.ton so long my thumb is going to fall off.'

'I've been standing here longer,' Hyperion grumbled. 'You two guard the Doors while I go up to the mortal world. I have some Greek heroes to wreak vengeance upon!'

'Oh, no!' Krios complained. 'That Roman boy is on his way to Epirus the one who killed me on Mount Othrys. Got lucky, he did. Now it's my turn.'

'Bah!' Hyperion drew his sword. 'I'll gut you first, Ram-head!'

Krios raised his own blade. 'You can try, but I won't be stuck in this stinking pit any longer!'

Annabeth caught Percy's eyes. She mouthed: One, two Before he could strike the chains, a high-pitched whine pierced his ears, like the sound of an incoming rocket. Percy just had time to think: Uh-oh. Then an explosion rocked the hillside. A wave of heat knocked Percy backwards. Dark shrapnel ripped through Krios and Hyperion, shredding them as easily as wood in a chipper.

STINKING PIT. A hollow voice rolled across the plains, shaking the warm fleshy ground.

Bob staggered to his feet. Somehow the explosion hadn't touched him. He swept his spear in front of him, trying to locate the source of the voice. Small Bob the kitten crawled into his coveralls.

Annabeth had landed about twenty feet from the Doors. When she stood, Percy was so relieved she was alive it took him a moment to realize she looked like herself. The Death Mist had evaporated.

He looked at his own hands. His disguise was gone too.

t.i.tANS, said the voice disdainfully. LESSER BEINGS. IMPERFECT AND WEAK.

In front of the Doors of Death, the air darkened and solidified. The being who appeared was so ma.s.sive, radiating such pure malevolence, that Percy wanted to crawl away and hide.

Instead, he forced his eyes to trace the G.o.d's form, starting with his black iron boots, each one as large as a coffin. His legs were covered in dark greaves; his flesh all thick purple muscle, like the ground. His armoured skirt was made from thousands of blackened, twisted bones, woven together like chain links and clasped in place by a belt of interlocking monstrous arms.

On the surface of the warrior's breastplate, murky faces appeared and submerged giants, Cyclopes, gorgons and drakons all pressing against the armour as if trying to get out.

The warrior's arms were bare muscular, purple and glistening his hands as large as crane scoops.

Worst of all was his head: a helmet of twisted rock and metal with no particular shape just jagged spikes and pulsing patches of magma. His entire face was a whirlpool an inward spiral of darkness. As Percy watched, the last particles of t.i.tan essence from Hyperion and Krios were vacuumed into the warrior's maw.

Somehow Percy found his voice. 'Tartarus.'

The warrior made a sound like a mountain cracking in half: a roar or a laugh, Percy couldn't be sure.

This form is only a small manifestation of my power, said the G.o.d. But it is enough to deal with you. I do not interfere lightly, little demiG.o.d. It is beneath me to deal with gnats such as yourself.

'Uh ...' Percy's legs threatened to collapse under him. 'Don't ... you know ... go to any trouble.'

You have proven surprisingly resilient, Tartarus said. You have come too far. I can no longer stand by and watch your progress.

Tartarus spread his arms. Throughout the valley, thousands of monsters wailed and roared, clashing their weapons and bellowing in triumph. The Doors of Death shuddered in their chains.

Be honoured, little demiG.o.ds, said the G.o.d of the pit. Even the Olympians were never worthy of my personal attention. But you will be destroyed by Tartarus himself!

LXV.

FRANK.

FRANK WAS HOPING FOR FIREWORKS.

Or at least a big sign that read: WELCOME HOME!

More than three thousand years ago, his Greek ancestor good old Periclymenus the shape-shifter had sailed east with the Argonauts. Centuries later, Periclymenus's descendants had served in the eastern Roman legions. Then, through a series of misadventures, the family had ended up in China, finally emigrating to Canada in the twentieth century. Now Frank was back in Greece, which meant that the Zhang family had completely circled the globe.

That seemed like cause for celebration, but the only welcoming committee was a flock of wild, hungry harpies who attacked the ship. Frank felt kind of bad as he shot them down with his bow. He kept thinking of Ella, their freakishly smart harpy friend from Portland. But these harpies weren't Ella. They gladly would have chewed Frank's face off. So he blasted them into clouds of dust and feathers.

The Greek landscape below was just as inhospitable. The hills were strewn with boulders and stunted cedars, all shimmering in the hazy air. The sun beat down as if trying to hammer the countryside into a Celestial bronze shield. Even from a hundred feet up, Frank could hear the drone of cicadas buzzing in the trees a sleepy, otherworldly sound that made his eyes heavy. Even the duelling voices of the war G.o.ds inside his head seemed to have dozed off. They had hardly bothered Frank at all since the crew had crossed into Greece.

Sweat trickled down his neck. After being frozen below deck by that crazy snow G.o.ddess, Frank had thought he would never feel warm again, but now the back of his shirt was soaked.

'Hot and steamy!' Leo grinned at the helm. 'Makes me homesick for Houston! What do you say, Hazel? All we need now are some giant mosquitoes, and it'll feel just like the Gulf Coast!'

'Thanks a lot, Leo,' Hazel grumbled. 'We'll probably get attacked by Ancient Greek mosquito monsters now.'

Frank studied the two of them, quietly marvelling how the tension between them had disappeared. Whatever had happened to Leo during his five days of exile, it had changed him. He still joked around, but Frank sensed something different about him like a ship with a new keel. Maybe you couldn't see the keel, but you could tell it was there by the way the ship cut through the waves.

Leo didn't seem so intent on teasing Frank. He chatted more easily with Hazel not stealing those wistful, mooning glances that had always made Frank uncomfortable.

Hazel had diagnosed the problem privately to Frank: 'He met someone.'

Frank was incredulous. 'How? Where? How could you possibly know?'

Hazel smiled. 'I just do.'