For what felt like the hundredth time in his life, Frank was glad to have gotten out unscathed. He felt ashamed for not being able to do it himself. Everything had been going so well until then. If only he'd had Percy's power of water manipulation.

As the magnificent palace came back into view, he wondered what would happen next. If Triton sent him on another quest, he would surely have some choice words for him. He was ready to head back to Camp Jupiter for some well-earned rest. But not before he finally did what he came to do – the reason he'd agreed to this quest in the first place.

He had considered taking Percy's advice and turning into a blowfish – but decided against it. In the end, he settled for a dolphin; sleek, silver, and smart. He swam back up to the surface for a breath of air that would last him a while. Just as he returned, he was greeted by a familiar face.

'Frank? Is that you?'

The cyclops blinked his large eye curiously at the dolphin.

Tyson! Hey! Yes, it's me.

'Yay!' Tyson pulled him into a slippery hug. Frank tried to wrap his fins around his relative in return. He was immensely glad that Triton was nowhere to be seen. He'd probably gloat about how he would have done the job so much better.

'I knew it was you because I saw a little fish turning into a dolphin. Daddy sent me to get you! Isn't that great!'

Very. Let's go.

As Tyson led him through the palace, he was able to get a proper look at some of the merfolk. They definitely weren't anything like the cartoons he'd grown up watching on TV – they all had skin in different shades of blue, razor-sharp fangs and eyes that glowed and burned like his father's, except they were green.

'You are a hero,' Tyson said. 'You made the big scary monster go away. You made it go BOOM! I was watching.'

You were? Thanks. I guess I am. But after the episode with Phorcys and Keto, Frank wasn't feeling much like a hero. More like a pushover.

They swam along a series of twisting corridors, the walls of which had shells of all kinds embedded into them in spiral patterns. Bright-coloured fish weaved around them and in and out of the large windows. Before long they came to a large, ornate set of doors, which were open a fraction. Blue light was spilling out through the tiny gap. Frank's heart skipped a few beats. This was it!

The throne room was breathtakingly beautiful. The floor was made of a thousand sea-green pearls and the ceiling consisted of a glittering mosaic depicting the most majestic and beautiful sea creatures and heroic battle scenes. Like many of the buildings, the walls were made of smooth, white abalone shell. Pillars were spaced around the walls, in tight spirals of gold, silver and aquamarine. And there, seated on a throne of coral, was Poseidon himself.

He looked like an older Percy. If Percy liked to wear bright-coloured Hawaiian shirts and had a beard. He also looked friendlier than his own dad, but that was only to be expected, since his dad was the god of war. Frank could feel the connection to him, even though they were separated by thousands of generations. Or maybe that was just because he was a dolphin.

'Hello, Tyson. And…ah.'

'I brought him, Daddy!' Tyson looked very pleased with himself.

'Yes, thank you, General. You may leave us now.'

As Tyson swam away, Poseidon looked down at Frank and gave him a warm smile. This helped alleviate some of his nerves…but not all of them.

'Hello, Frank Zhang. It's a pleasure to finally meet you.'

Er…hello. It's…it's a pleasure to meet you too…Lord Poseidon…Your Highness…Sir. If dolphins could blush, Frank was sure he would be. What was wrong with him?

The god chuckled.

'You must tell me all about what happened with Phorcys and Keto. But first, you may take your human form.'

But…I can't…

'Don't worry. I will protect you.'

For a moment, Frank thought he wouldn't be able to. He sometimes got stuck when he was stressed. That would be embarrassing to say the least. But he focused on the pearl floor and took a deep breath. His arms and legs returned as he morphed back into a teenaged boy. His purple praetor's cape fanned out behind him in the water. He sank into a low bow, holding his breath. Poseidon gave a nod of approval and snapped his fingers. Frank felt instantly warm and dry all over. A thin layer of oxygen was encasing his body, just as it had been during his underwater adventure with Leo and Hazel.

'You have not wasted my gift, Frank. I particularly liked the Portuguese man-of-war. Very clever. And very fitting. I don't believe I've ever had a child of Mars in my palace before. You are the first of your kind.'

Frank didn't know what to say to this. 'Thank you?' 'Yes, aren't I awesome?' Instead, the words that came out were:

'It wasn't actually my idea. A fish-centaur guy suggested it.' In his nervousness, he forgot the actual name for them. 'And the rest of it I planned with my friends. So…'

Poseidon laughed. His voice echoed round the throne room.

'You are far too modest. Being able to work with others and accept help is a quality a great leader must have.'

'You helped me.'

'I did. Do not worry. After you defeated the Skolopendra for me, it was the least I could do. But I can tell that it is troubling you.'

'Oh…no. It's nothing.'

He raised a dark eyebrow.

'Really?'

'It's just…Percy would have been able to do it.' He cursed himself for sounding so silly and childish. 'Not that I'm ungrateful! Really! In fact, I actually did all this so I could thank you. So…um…thanks.'

His sea-green eyes sparkled with amusement.

'You are very welcome. And yes, you are not my son. But you do not need to be. You are an exceptionally powerful demigod. Your abilities are more than enough, as you know. But we have digressed. Tell me all about what you found.'

Frank told him all about the hidden cave and the enslaved sea creatures.

'Hmm. That is concerning. But nothing that can't be fixed. I'm sure Triton will be able to take care of it.'

Frank tried to hide his grin. He was sure that his relative would love having to get off his behind and go face the god and goddess himself.

'Now that we know where the pair are hiding, stopping them from sending more of their children to attack the palace should not be too hard. We can...relocate them to some corner of the ocean where they will not cause any more trouble. Or another landlocked city. Yes, that will do.'

'That sounds like a good idea,' Frank agreed.

'Now, I believe it is about time you returned to your friends at camp. They are beginning to worry.'

'They are?' Frank suddenly thought of Hazel, Reyna, Percy, and Annabeth. 'They're very worried?'

'Not too much. They have faith in you. But you should not keep them waiting any longer. I will need to assist you with this. Rainbow the hippocampus is resting. He is very tired.'

'Thank you, sir.' Frank bowed once more. Poseidon gave him one last smile before he felt the water close in on him. This time, it wasn't suffocating. More like he was floating, being carried away, far away...

'How did it go, Frank? Did you kick its butt?' Percy asked enthusiastically.

'I sure did. Or rather, burnt its mouth.'

'Way to go!' They high-fived.

The small group of friends were gathered near a fountain in New Rome, watching the early evening sunset. Frank had arrived at the Fifth Cohort barracks, where he'd found Hazel, and then gone back to his house, where he'd taken a three-hour nap. Hazel had let the others know that he was back, in one piece and indeed in human form.

'I knew you could do it,' Hazel beamed with pride. 'I wish I could have seen it.'

'It sounds like you did very well, Praetor Zhang,' said Reyna.

'I also had a run-in with Porky and Kate.' Frank recounted everything that had happened. His friends believed every word straight away. After all they'd been through, there was no way they wouldn't.

'They enslaved a bunch of sea creatures?' Percy's brow furrowed. 'Man, they really need to stop doing that.'

'It's okay. Your dad said they'd take care of it.'

'Wicked.'

'Anyway, how was your day?'

'Awesome!' Annabeth piped up. 'I can't wait to go to college!' Frank could tell she wasn't kidding - she had about a dozen brochures and leaflets clutched in her arms. 'It's all designed for demigods – everything's dyslexia friendly, they're super understanding of all our powers, and we won't have to worry about monster attacks. Even Percy couldn't get kicked out of this place!'

'Hey!' Percy elbowed her in the ribs.

'That's great, Annabeth,' laughed Reyna. 'Why don't you tell us the rest of the story, Frank?'

Frank then recounted the final part of his adventure. Percy grinned from ear to ear.

'See? I told you it would be fine. Although it's hilarious that you called him Your Highness.'

Frank's cheeks burned.

'I was freaking out, okay?'

'Which is totally understandable,' Hazel defended him. 'I'm really happy for you, Frank.'

'Me too, bro,' said Percy. 'I'm just messing with you.'

'Now you have to deal with something else,' said Reyna. 'All the legionnaires have been asking after you all day. They're going to want to hear your story. So be prepared for that!'

'That's true,' said Hazel. 'It's all the Fifth have been talking about.'

Frank laughed.

'Well, I guess I can't keep them waiting. Let's head to dinner. I'm starving. You guys can come too!' he told Percy and Annabeth.

'Thanks, Frank, we'd love to. It doesn't sound like you'll get much chance to eat, though,' said Annabeth.

'Never mind. I'm looking forward to telling everyone this story.'

'I'll make sure you don't exaggerate anything,' Percy teased.

'He doesn't need to,' said Hazel, taking his hand as they began to head out of the city towards Camp Jupiter. 'It sounds like you had quite the adventure!'