So why did the idea fill him with dread? He felt guilty about leaving Reyna to rule without him, but still ... part of him wanted to go back to Camp Half-Blood with Piper and Leo. He guessed that that made him a pretty terrible leader.

'Jason?' Leo asked. 'Argo II to Jason. Come in.'

He realized his friends were looking at him expectantly. They needed rea.s.surance. Whether or not he made it back to New Rome after the war, Jason had to step up now and act like a praetor.

'Yeah, sorry.' He touched the groove that Sciron the bandit had cut in his hair. 'Crossing the Atlantic is a hard journey, no doubt. But I'd never bet against Reyna. If anyone can make it, she will.'

Piper circled her spoon through her soup. Jason was still a little nervous about her getting jealous of Reyna, but when she looked up she gave him a dry smile that seemed more teasing than insecure.

'Well, I'd love to see Reyna again,' she said. 'But how is she supposed to find us?'

Frank raised his hand. 'Can't you just send her an Iris-message?'

'They're not working very well,' Coach Hedge put in. 'Horrible reception. Every night, I swear, I could kick that rainbow G.o.ddess ...'

He faltered. His face turned bright red.

'Coach?' Leo grinned. 'Who have you been calling every night, you old goat?'

'No one!' Hedge snapped. 'Nothing! I just meant '

'He means we've already tried,' Hazel intervened, and the coach gave her a grateful look. 'Some magic is interfering ... maybe Gaia. Contacting the Romans is even harder. I think they're shielding themselves.'

Jason looked from Hazel to the coach, wondering what was going on with the satyr and how Hazel knew about it. Now that Jason thought about it, the coach hadn't mentioned his cloud nymph girlfriend Mellie in a long time ...

Frank drummed his fingers on the table. 'I don't suppose Reyna has a cell phone ...? Nah. Never mind. She'd probably have bad reception on a pegasus flying over the Atlantic.'

Jason thought about the Argo II's journey across the ocean, the dozens of encounters that had nearly killed them. Thinking about Reyna making that journey alone he couldn't decide whether it was terrifying or awe-inspiring.

'She'll find us,' he said. 'She mentioned something in the dream she's expecting me to go to a certain place on our way to the House of Hades. I I'd forgotten about it, actually, but she's right. It's a place I need to visit.'

Piper leaned towards him, her caramel braid falling over her shoulder. Her multicoloured eyes made it hard for him to think straight.

'And where is this place?' she asked.

'A ... uh, a town called Split.'

'Split.' She smelled really good like blooming honeysuckle.

'Um, yeah.' Jason wondered if Piper was working some sort of Aphrodite magic on him like maybe every time he mentioned Reyna's name she would befuddle him so much he couldn't think about anything but Piper. He supposed it wasn't the worst sort of revenge. 'In fact, we should be getting close. Leo?'

Leo punched the intercom b.u.t.ton. 'How's it going up there, buddy?'

Festus the figurehead creaked and steamed.

'He says maybe ten minutes to the harbour,' Leo reported. 'Though I still don't get why you want to go to Croatia, especially a town called Split. I mean, you name your city Split, you gotta figure it's a warning to, you know, split. Kind of like naming your city Get Out!'

'Wait,' Hazel said. 'Why are we going to Croatia?'

Jason noticed that the others were reluctant to meet her eyes. Since her trick with the Mist against Sciron the bandit, even Jason felt a little nervous around her. He knew that wasn't fair to Hazel. It was hard enough being a child of Pluto, but she'd pulled off some serious magic on that cliff. And afterwards, according to Hazel, Pluto himself had appeared to her. That was something Romans typically called a bad omen.

Leo pushed his chips and hot sauce aside. 'Well, technically we've been in Croatian territory for the past day or so. All that coastline we've been sailing past is it, but I guess back in the Roman times it was called ... what'd you say, Jason? Bodacious?'

'Dalmatia,' Nico said, making Jason jump.

Holy Romulus ... Jason wished he could put a bell around Nico di Angelo's neck to remind him the guy was there. Nico had this disturbing habit of standing silently in the corner, blending into the shadows.

He stepped forward, his dark eyes fixed on Jason. Since they'd rescued him from the bronze jar in Rome, Nico had slept very little and eaten even less, as if he were still subsisting on those emergency pomegranate seeds from the Underworld. He reminded Jason a little too much of a flesh-eating ghoul he'd once fought in San Bernardino.

'Croatia used to be Dalmatia,' Nico said. 'A major Roman province. You want to visit Diocletian's Palace, don't you?'

Coach Hedge managed another heroic belch. 'Whose palace? And is Dalmatia where those Dalmatian dogs come from? That 101 Dalmatians movie I still have nightmares.'

Frank scratched his head. 'Why would you have nightmares about that?'

Coach Hedge looked like he was about to launch into a major speech about the evils of cartoon Dalmatians, but Jason decided he didn't want to know.

'Nico is right,' he said. 'I need to go to Diocletian's Palace. It's where Reyna will go first, because she knows I would go there.'

Piper raised an eyebrow. 'And why would Reyna think that? Because you've always had a mad fascination with Croatian culture?'

Jason stared at his uneaten sandwich. It was hard to talk about his life before Juno wiped his memory. His years at Camp Jupiter seemed made up, like a movie he'd acted in decades before.

'Reyna and I used to talk about Diocletian,' he said. 'We both kind of idolized the guy as a leader. We talked about how we'd like to visit Diocletian's Palace. Of course we knew that was impossible. No one could travel to the ancient lands. But still we made this pact that if we ever did that's where we'd go.'

'Diocletian ...' Leo considered the name, then shook his head. 'I got nothing. Why was he so important?'

Frank looked offended. 'He was the last great pagan emperor!'

Leo rolled his eyes. 'Why am I not surprised you know that, Zhang?'

'Why wouldn't I? He was the last one who worshipped the Olympian G.o.ds, before Constantine came along and adopted Christianity.'

Hazel nodded. 'I remember something about that. The nuns at St Agnes taught us that Diocletian was a huge villain, right along with Nero and Caligula.' She looked askance at Jason. 'Why would you idolize him?'

'He wasn't a total villain,' Jason said. 'Yeah, he persecuted Christians, but otherwise he was a good ruler. He worked his way up from nothing by joining the legion. His parents were former slaves ... or at least his mom was. DemiG.o.ds know he was a son of Jupiter the last demiG.o.d to rule Rome. He was also the first emperor ever to retire, like, peacefully, and give up his power. He was from Dalmatia, so he moved back there and built a retirement palace. The town of Split grew up around ...'

He faltered when he looked at Leo, who was mimicking taking notes with an air pencil.

'Go on, Professor Grace!' he said, wide-eyed. 'I wanna get an A on the test.'

'Shut up, Leo.'

Piper sipped another spoonful of soup. 'So why is Diocletian's Palace so special?'

Nico leaned over and plucked a grape. Probably that was the guy's entire diet for the day. 'It's said to be haunted by the ghost of Diocletian.'

'Who was a son of Jupiter, like me,' Jason said. 'His tomb was destroyed centuries ago, but Reyna and I used to wonder if we could find Diocletian's ghost and ask where he was buried ... well, according to the legends, his sceptre was buried with him.'

Nico gave him a thin, creepy smile. 'Ah ... that legend.'

'What legend?' Hazel asked.

Nico turned to his sister. 'Supposedly Diocletian's sceptre could summon the ghosts of the Roman legions, any of them who worshipped the old G.o.ds.'

Leo whistled. 'Okay, now I'm interested. Be nice to have a booty-kicking army of pagan zombies on our side when we enter the House of Hades.'

'Not sure I would've put it that way,' Jason muttered, 'but yeah.'

'We don't have much time,' Frank warned. 'It's already July ninth. We have to get to Epirus, close the Doors of Death '

'Which are guarded,' Hazel murmured, 'by a smoky giant and a sorceress who wants ...' She hesitated. 'Well, I'm not sure. But according to Pluto, she plans to "rebuild her domain". Whatever that means, it's bad enough that my dad felt like warning me personally.'

Frank grunted. 'And, if we survive all that, we still have to find out where the giants are waking Gaia and get there before the first of August. Besides, the longer Percy and Annabeth are in Tartarus '

'I know,' Jason said. 'We won't take long in Split. But looking for the sceptre is worth a try. While we're at the palace, I can leave a message for Reyna, letting her know the route we're taking for Epirus.'

Nico nodded. 'The sceptre of Diocletian could make a huge difference. You'll need my help.'

Jason tried not to show his discomfort, but his skin p.r.i.c.kled at the thought of going anywhere with Nico di Angelo.

Percy had shared some disturbing stories about Nico. His loyalties weren't always clear. He spent more time with the dead than the living. Once, he'd lured Percy into a trap in the palace of Hades. Maybe Nico had made up for that by helping the Greeks against the t.i.tans, but still ...

Piper squeezed his hand. 'Hey, sounds fun. I'll go, too.'

Jason wanted to yell: Thank the G.o.ds!

But Nico shook his head. 'You can't, Piper. It should only be Jason and me. Diocletian's ghost might appear for a son of Jupiter, but any other demiG.o.ds would most likely ... ah, spook him. And I'm the only one who can talk to his spirit. Even Hazel won't be able to do that.'

Nico's eyes held a gleam of challenge. He seemed curious as to whether or not Jason would protest.

The ship's bell sounded. Festus creaked and whirred over the loudspeaker.

'We've arrived,' Leo announced. 'Time to Split.'

Frank groaned. 'Can we leave Valdez in Croatia?'

Jason stood. 'Frank, you're in charge of defending the ship. Leo, you've got repairs to do. The rest of you, help out wherever you can. Nico and I ...' He faced the son of Hades. 'We have a ghost to find.'

x.x.xV.

JASON.

JASON FIRST SAW THE ANGEL AT THE ICE-CREAM CART.

The Argo II had anch.o.r.ed in the bay along with six or seven cruise ships. As usual, the mortals didn't pay the trireme any attention, but, just to be safe, Jason and Nico hopped on a skiff from one of the tourist boats so they would look like part of the crowd when they came ash.o.r.e.

At first glance, Split seemed like a cool place. Curving around the harbour was a long esplanade lined with palm trees. At the sidewalk cafes, European teenagers were hanging out, speaking a dozen different languages and enjoying the sunny afternoon. The air smelled of grilled meat and fresh-cut flowers.

Beyond the main boulevard, the city was a hodgepodge of mediaeval castle towers, Roman walls, limestone town houses with red-tiled roofs and modern office buildings all crammed together. In the distance, grey-green hills marched towards a mountain ridge, which made Jason a little nervous. He kept glancing at that rocky escarpment, expecting the face of Gaia to appear in its shadows.

Nico and he were wandering along the esplanade when Jason spotted a guy with wings buying an ice-cream bar from a street cart. The vendor lady looked bored as she counted the guy's change. Tourists navigated around the angel's huge wings without a second glance.

Jason nudged Nico. 'Are you seeing this?'

'Yeah,' Nico agreed. 'Maybe we should buy some ice cream.'

As they made their way towards the street cart, Jason worried that this winged dude might be a son of Boreas the North Wind. At his side, the angel carried the same kind of jagged bronze sword the Boreads had, and Jason's last encounter with them hadn't gone so well.

But this guy seemed more chill than chilly. He wore a red tank top, Bermuda shorts and huarache sandals. His wings were a combination of russet colours, like a bantam rooster or a lazy sunset. He had a deep tan and black hair almost as curly as Leo's.

'He's not a returned spirit,' Nico murmured. 'Or a creature of the Underworld.'

'No,' Jason agreed. 'I doubt they would eat chocolate-covered ice-cream bars.'

'So what is he?' Nico wondered.

They got within thirty feet, and the winged dude looked directly at them. He smiled, gestured over his shoulder with his ice-cream bar and dissolved into the air.

Jason couldn't exactly see him, but he'd had enough experience controlling the wind that he could track the angel's path a warm wisp of red and gold zipping across the street, spiralling down the sidewalk and blowing postcards from the carousels in front of the tourist shops. The wind headed towards the end of the promenade, where a big fortress-like structure loomed.

'I'm betting that's the palace,' Jason said. 'Come on.'

Even after two millennia, Diocletian's Palace was still impressive. The outer wall was only a pink granite sh.e.l.l, with crumbling columns and arched windows open to the sky, but it was mostly intact, a quarter mile long and seventy or eighty feet tall, dwarfing the modern shops and houses that huddled beneath it. Jason imagined what the palace must have looked like when it was newly built, with Imperial guards walking the ramparts and the golden eagles of Rome glinting on the parapets.

The wind angel or whatever he was whisked in and out of the pink granite windows, then disappeared on the other side. Jason scanned the palace's facade for an entrance. The only one he saw was several blocks away, with tourists lined up to buy tickets. No time for that.

'We've got to catch him,' Jason said. 'Hold on.'

'But '

Jason grabbed Nico and lifted them both into the air.

Nico made a m.u.f.fled sound of protest as they soared over the walls and into a courtyard where more tourists were milling around, taking pictures.

A little kid did a double take when they landed. Then his eyes glazed over and he shook his head, like he was dismissing a juice-box-induced hallucination. No one else paid them any attention.