‘Give the chariot back.’ I tried to keep my voice even. ‘I took on your dad once. You don’t scare me.’

Phobos laughed. ‘Nothing to fear but fear itself. Isn’t that what they say? Well, let me tell you a little secret, half-blood. I am fear. If you want to find the chariot, come and get it. It’s across the water. You’ll find it where the little wild animals live – just the sort of place you belong.’

He snapped his fingers and disappeared in a cloud of yellow vapour.

Now, I’ve got to tell you, I’ve met a lot of godlings and monsters I didn’t like, but Phobos took the prize. I don’t like bullies. I’d never been in the ‘A’ crowd at school, so I’d spent most of my life standing up to punks who tried to frighten me and my friends. The way Phobos laughed at me and made Clarisse collapse just by looking at her… I wanted to teach this guy a lesson.

I helped Clarisse up. Her face was still beaded with sweat.

‘Now are you ready for help?’ I asked.

We took the subway, keeping a lookout for more attacks, but no one bothered us. As we rode, Clarisse told me about Phobos and Deimos.

‘They’re minor gods,’ she said. ‘Phobos is fear. Deimos is terror.’

‘What’s the difference?’

She frowned. ‘Deimos is bigger and uglier, I guess. He’s good at freaking out entire crowds. Phobos is more, like, personal. He can get inside your head.’

‘That’s where they get the word phobia?’

‘Yeah,’ she grumbled. ‘He’s so proud of that. All those phobias named after him. The jerk.’

‘So why don’t they want you driving the chariot?’

‘It’s usually a ritual just for Ares’s sons when they turn fifteen. I’m the first daughter to get a shot in a long time.’

‘Good for you.’

‘Tell that to Phobos and Deimos. They hate me. I’ve got to get the chariot back to the temple.’

‘Where is the temple?’

‘Pier 86. The Intrepid.’

‘Oh.’ It made sense, now that I thought about it. I’d never actually been on board the old aircraft carrier, but I knew they used it as some kind of military museum. It probably had a bunch of guns and bombs and other dangerous toys. Just the kind of place a war god would want to hang out.

‘We’ve got maybe four hours before sunset,’ I guessed. ‘That should be enough time if we can find the chariot.’

‘But what did Phobos mean, “over the water”? We’re on an island, for Zeus’s sake. That could be any direction!’

‘He said something about wild animals,’ I remembered. ‘Little wild animals.’

‘A zoo?’

I nodded. A zoo over the water could be the one in Brooklyn, or maybe… someplace harder to get to, with little wild animals. Someplace nobody would ever think to look for a war chariot.

‘Staten Island,’ I said. ‘They’ve got a small zoo.’

‘Maybe,’ Clarisse said. ‘That sounds like the kind of out-of-the-way place Phobos and Deimos would stash something. But if we’re wrong –’

‘We don’t have time to be wrong.’

We hopped off the train at Times Square and caught the Number 1 line downtown, towards the ferry terminal.

We boarded the Staten Island Ferry at three thirty, along with a bunch of tourists, who crowded the railings of the top deck, snapping pictures as we passed the Statue of Liberty.

‘He modelled that on his mom,’ I said, looking up at the statue.

Clarisse frowned at me. ‘Who?’

‘Bartholdi,’ I said. ‘The dude who made the Statue of Liberty. He was a son of Athena, and he designed it to look like his mom. That’s what Annabeth told me, anyway.’

Clarisse rolled her eyes. Annabeth was my best friend and a huge nut when it came to architecture and monuments. I guess her egghead facts rubbed off on me sometimes.

‘Useless,’ Clarisse said. ‘If it doesn’t help you fight, it’s useless information.’

I could’ve argued with her, but just then the ferry lurched like it had hit a rock. Tourists spilled forward, tumbling into each other. Clarisse and I ran to the front of the boat. The water below us started to boil. Then the head of a sea serpent erupted from the bay.

The monster was at least as big as the boat. It was grey and green with a head like a crocodile and razor-sharp teeth. It smelled… well, like something that had just come up from the bottom of New York Harbor. Riding on its neck was a bulky guy in black Greek armour. His face was covered with ugly scars, and he held a javelin in his hand.

‘Deimos!’ Clarisse yelled.

‘Hello, sister!’ His smile was almost as horrible as the serpent’s. ‘Care to play?’

The monster roared. Tourists screamed and scattered. I don’t know exactly what they saw. The Mist usually prevents mortals from seeing monsters in their true form, but whatever they saw, they were terrified.

‘Leave them alone!’ I yelled.

‘Or what, son of the sea god?’ Deimos sneered. ‘My brother tells me you’re a wimp! Besides, I love terror. I live on terror!’

He spurred the sea serpent into head-butting the ferry, which sloshed backwards. Alarms blared. Passengers fell over each other trying to get away. Deimos laughed with delight.

‘That’s it,’ I grumbled. ‘Clarisse, grab on.’

‘What?’

‘Grab onto my neck. We’re going for a ride.’

She didn’t protest. She grabbed onto me, and I said, ‘One, two, three – JUMP!’

We leaped off the top deck and straight into the bay, but we were only underwater for a moment. I felt the power of the ocean surging through me. I willed the water to swirl around me, building force until we burst out of the bay on top of a ten-metre-high waterspout. I steered us straight towards the monster.

‘You think you can tackle Deimos?’ I yelled to Clarisse.

‘I’m on it!’ she said. ‘Just get me within three metres.’

We barrelled towards the serpent. Just as it bared its fangs, I swerved the waterspout to one side, and Clarisse jumped. She crashed into Deimos, and both of them toppled into the sea.

The sea serpent came after me. I quickly turned the waterspout to face him, then summoned all my power and willed the water to even greater heights.

WHOOOOM!

Fifty thousand litres of salt water crashed into the monster. I leaped over its head, uncapped Riptide, and slashed with all my might at the creature’s neck. The monster roared. Green blood spouted from the wound, and the serpent sank beneath the waves.

I dived underwater and watched as it retreated to the open sea. That’s one good thing about sea serpents: they’re big babies when it comes to getting hurt.

Clarisse surfaced near me, spluttering and coughing. I swam over and grabbed her.

‘Did you get Deimos?’ I asked.

Clarisse shook her head. ‘The coward disappeared as we were wrestling. But I’m sure we’ll see him again. Phobos, too.’

Tourists were still running around the ferry in a panic, but it didn’t look like anybody was hurt. The boat didn’t seem damaged. I decided we shouldn’t stick around. I held onto Clarisse’s arm and willed the waves to carry us towards Staten Island.

In the west, the sun was going down over the Jersey shore. We were running out of time.

I’d never spent much time on Staten Island, and I found it was a lot bigger than I thought and not much fun to walk. The streets curved around confusingly, and everything seemed to be uphill. I was dry (I never got wet in the ocean unless I wanted to) but Clarisse’s clothes were still sopping wet, so she left mucky footprints all over the sidewalk, and the bus driver wouldn’t let us on the bus.

‘We’ll never make it in time,’ she sighed.

‘Stop thinking that way.’ I tried to sound upbeat, but I was starting to have doubts too. I wished we had reinforcements. Two demigods against two minor gods was not an even match, and when we met Phobos and Deimos together, I wasn’t sure what we were going to do. I kept remembering what Phobos had said: How about you, Percy Jackson? What do you fear? I’ll find out, you know.

After dragging ourselves halfway down the island, past a lot of suburban houses, a couple of churches and a McDonald’s, we finally saw a sign that said ZOO. We turned a corner and followed this curvy street with some woods on one side until we came to the entrance.

The lady at the ticket booth looked at us suspiciously, but thank the gods I had enough cash to get us inside.

We walked around the reptile house, and Clarisse stopped in her tracks.

‘There it is.’

It was sitting at a crossroads between the petting zoo and the sea otter pond: a large golden and red chariot tethered to four black horses. The chariot was decorated with amazing detail. It would’ve been beautiful if all the pictures hadn’t shown people dying painful deaths. The horses were breathing fire out of their nostrils.

Families with buggies walked right past the chariot like it didn’t exist. I guess the Mist must’ve been really strong around it, because the chariot’s only camouflage was a handwritten note taped to one of the horses’ chests that said OFFICIAL ZOO VEHICLE.

‘Where are Phobos and Deimos?’ Clarisse muttered, drawing her sword.

I couldn’t see them anywhere, but this had to be a trap.

I concentrated on the horses. Usually I could talk to horses, since my dad had created them. I said, Hey. Nice fire-breathing horses. Come here!

One of horses whinnied disdainfully. I could understand his thoughts, all right. He called me some names I can’t repeat.

‘I’ll try to get the reins,’ Clarisse said. ‘The horses know me. Cover me.’

‘Right.’ I wasn’t sure how I was supposed to cover her with a sword, but I kept my eyes peeled as Clarisse approached the chariot. She walked around the horses, almost tiptoeing.

She froze as a lady with a three-year-old girl passed by. The girl said, ‘Pony on fire!’

‘Don’t be silly, Jessie,’ the mother said in a dazed voice. ‘That’s an official zoo vehicle.’

The little girl tried to protest, but the mother grabbed her hand and they kept walking. Clarisse got closer to the chariot. Her hand had almost reached the rail when the horses reared up, whinnying and breathing flames. Phobos and Deimos appeared in the chariot, both of them now dressed in pitch-black battle armour. Phobos grinned, his red eyes glowing. Deimos’s scarred face looked even more horrible up close.

‘The hunt is on!’ Phobos yelled. Clarisse stumbled back as he lashed the horses and charged the chariot straight towards me.

Now, I’d like to tell you that I did something heroic, like stand up against a raging team of fire-breathing horses with only my sword. The truth is, I ran. I jumped over a trashcan and an exhibit fence, but there was no way I could outrun the chariot. It crashed through the fence right behind me, ploughing down everything in its path.

‘Percy, look out!’ Clarisse yelled, like I needed somebody to tell me that.