AFTER FRANK SUMMONED some more ghosts to lead them through some really dark tunnels ( which was lowkey sick, to be honest ) down to the Doors of Death, they emerged facing a giant that looked like he wanted to die today. Kat could relate.

So, naturally, they went to kill the giant.

They attacked him from every direction — Leo shooting fire at his legs, Frank and Piper jabbing at his chest, Jason flying into the air and kicking him in the face. Kat called upon Cortana to slash at him while she sped around as a distraction.

Each time the giant's smoky veil started creeping around one of them, Nico was there, slashing through it, drinking in the darkness with his Stygian blade.

The giant — Clytius, Kat thought his name was — snarled, turning back and forth as if he couldn't decide which of them to kill first. Wait! Hold still! No! Ouch!

The darkness around him dispelled completely, leaving nothing to protect him except his battered armor. Ichor oozed from a dozen wounds. The damage healed almost as fast as it was inflicted, but Kat could tell the giant was tiring.

One last time Jason flew at him, kicking him in the chest, and the giant's breastplate shattered. Clytius staggered backward. His sword dropped to the floor. He fell to his knees, and the demigods encircled him.

Only then did the goddess in the room that Kat had glimpsed at while running, Hecate, step forward, her torches raised. Mist curled around the giant, hissing and bubbling as it touched his skin.

"And so it ends," said Hecate.

It does not end. Clytius's voice echoed from somewhere above, muffled and slurred. My brethren have risen. Gaea waits only for the blood of Olympus. It took all of you together to defeat me. What will you do when the Earth Mother opens her eyes?

Hecate turned her torches upside down. She thrust them like daggers at Clytius's head. The giant's hair went up faster than dry tinder, spreading down his head and across his body until the heat of the bonfire made Kat wince. Clytius fell without a sound, face-first in the rubble of Hades's altar. His body crumbled to ashes.

For a moment, no one spoke.

The goddess Hecate faced Hazel. "You should go now, Hazel Levesque. Lead your friends out of this place."

Hazel gritted her teeth, her eyes flashingwith anger. "Just like that? No 'thank you'? No 'good work'?"

Kat learned a long time ago that the gods never gave praise. That didn't mean it was fair, however.

The goddess tilted her head. The weasel on her shoulder chittered — maybe a good-bye, maybe a warning — and disappeared in the folds of her mistress's skirts.

"You look in the wrong place for gratitude," said Hecate, which was just shitty. "As for 'good work,' that remains to be seen. Speed your way to Athens. Clytius was not wrong. The giants have risen — all of them, stronger than ever. Gaea is on the very edge of waking. The Feast of Hope will be poorly named unless you arrive to stop her."

The chamber rumbled. A stela crashed to the floor and shattered.

"The House of Hades is unstable," warned Hecate. "Leave now. We shall meet again."

The goddess dissolved. The Mist evaporated.

"She's friendly," Percy grumbled.

The crew turned toward him and Annabeth, as if just realizing they were there.

"Dude." Jason gave Percy a bear hug.

"Back from Tartarus!" Leo whooped. "That's my peeps!"

Piper threw her arms around Annabeth and cried.

Kat grinned at Leo and pulled him into a hug, nearly letting out a sigh of relief. He was here. He was alive. Being separated from him had been one of the worst feelings, after not being separated for, like, over a week, including their time at Ogygia.

This was a horrible coping mechanism, Kat knew. But for now, she didn't care, and she'd grow out of it. Probably not by choice, but hey. That's life.

"I would've never forgiven myself if you were dead," she whispered to him.

"But I'm alive, aren't I?" he pulled away and sent her a smirk, though it felt more real than his usual smirk. "I would've done the same, though."

"Yeah, but I had everyone else," she said. "You only had Hazel."

"I know. Sorry."

"It's not like you could control it," she rolled her eyes. "Just—"

Above them, duh, the ceiling shuddered. Cracks appeared in the remaining tiles. Columns of dust spilled down.

"We've got to get out of here," Jason said. "Uh, Frank . . .?"

Frank shook his head. "I think one favor from the dead is all I can manage today."

"Wait, what?" asked Hazel.

Piper raised her eyebrows. "Your unbelievable boyfriend called in a favor as a child of Mars. He summoned the spirits of some dead warriors, made them lead us here through . . . um, well, I'm not sure, actually. The passages of the dead? All I know is that it was very, very dark."

To their left, a section of the wall split. Two ruby eyes from a carved stone skeleton popped out and rolled across the floor.

"We'll have to shadow-travel," said Hazel.

Nico winced. "Hazel, I can barely manage that with only myself. With eight more people—"

"I'll help you," Hazel said, half-confidently. And, you know, that was enough for Kat.

An entire section of tiles peeled loose from the ceiling. And, well, that.

"Everyone, grab hands!" Nico yelled.

They made a hasty circle. The cavern collapsed, and she felt herself dissolving into shadow.

They appeared on the hillside overlooking the River Acheron. The sun was just rising, making the water glitter and the clouds glow orange. The cool morning air smelled of honeysuckle.

Kat was holding hands with Leo on her left, Piper on her right. They were all alive and mostly whole. The sunlight in the trees was the most beautiful thing she'd ever seen. She wanted to live in that moment — free of monsters and gods and evil spirits.

Then the others began to stir.

Nico realized that he was holding Percy's hand and quickly let go.

Leo staggered backward, taking Kat with him. "You know . . . I think I'll sit down."

He collapsed. Everyone joined him, falling like dominoes. The Argo II still floated over the river a few hundred yards away. Kat knew that they should signal Hedge and tell him they were alive. Had they been in the temple all night? Or several nights? But at the moment, the group was too tired to do anything except sit and relax and marvel at the fact that they were okay.

They began to exchange stories.

Frank explained what had happened with the ghostly legion and the army of monsters — how Nico had used the scepter of Diocletian, and how bravely Jason, Piper, and Kat had fought.

"Frank is being modest," said Jason. "He controlled the entire legion. You should've seen him. Oh, by the way . . ." Jason glanced at Percy. "I resigned my office, gave Frank a field promotion to praetor. Unless you want to contest that ruling."

Percy grinned. "No argument here."

"Praetor?" Hazel stared at Frank.

He shrugged uncomfortably. "Well . . . yeah. I know it seems weird."

She tried to throw her arms around him, then winced. She settled for kissing him. "It seems perfect."

Leo clapped Frank on the shoulder. "Way to go, Zhang. Now you can order Octavian to fall on his sword."

"Tempting," Frank agreed. He turned apprehensively to Percy. "But, you guys . . . Tartarus has to be the real story. What happened down there? How did you . . .?"

Percy laced his fingers through Annabeth's.

"We'll tell you the story," he promised. "But not yet, okay? I'm not ready to remember that place."

"No," Annabeth agreed. "Right now . . ." She gazed toward the river and faltered. "Uh, I think our ride is coming."

Kat turned to look. The Argo II veered to port, its aerial oars in motion, its sails catching the wind. Festus's head glinted in the sunlight. Even from a distance, she could hear him creaking and clanking in jubilation.

"That's my boy!" Leo yelled.

As the ship got closer, Kat saw Coach Hedge standing at the prow.

"About time!" the coach yelled down. He was doing his best to scowl, but his eyes gleamed as if maybe, just maybe, he was happy to see them. "What took you so long, cupcakes? You kept your visitor waiting!"

"Visitor?" Kat heard Hazel murmur.

At the rail next to Coach Hedge, a dark-haired girl appeared wearing a purple cloak, her face so covered with soot and bloody scratches that Kat almost didn't recognize her.

Reyna had arrived.