“Hey, you all,” Halfborn called from the ship. “We’re loaded up and ready to sail. What are you gabbing about? Come on!”

I looked at Amir, as well-groomed as always, his clothes spotless and perfectly ironed, his dark hair cut to razor-straight perfection. You’d never guess he was a guy who was probably weak from hunger and thirst. But his facial muscles were more taut than usual. His gentle brown eyes kept blinking like he was expecting a drop of cold water to splash on his forehead. Amir was suffering, but it was from something that had nothing to do with Ramadan.

“Just be careful,” he pleaded. “All of you. Magnus, I’d ask you to watch out for Samirah, but if I did that, she would hit me with her ax.”

“I would never hit you with my ax,” Sam said. “Anyway, I’ll be watching out for Magnus, not the other way around.”

“I’ll watch out for Sam,” Alex volunteered. “That’s what family is for, right?”

Amir blinked even more. I got the sense that he still wasn’t sure what to make of Alex Fierro, Sam’s green-haired gender-fluid half-sibling chaperone of doom.

“Okay.” Amir nodded. “Thanks.”

I couldn’t help feeling guilty about Amir’s anguish. Months ago, when he’d started seeing into Samirah’s weird double life as a Valkyrie of Odin, I’d healed his mind to keep him from going insane. Now his mortal eyes were permanently opened. Rather than living in blissful ignorance, he could see the earth giants that occasionally strolled down Commonwealth Avenue, the sea serpents that frolicked in the Charles River, and the Valkyries that flew overhead, bringing souls of fallen heroes to check in at the Hotel Valhalla. He could even see our huge Viking warship that looked like a heavily armed banana.

“We’ll be careful,” I told him. “Besides, nobody would dare attack this ship. It’s way too yellow.”

He mustered a faint smile. “That much is true.” He reached behind him. From the hood of his car, he hefted a large green insulated pack—the kind Fadlan’s Falafel used for deliveries. “This is for you, Magnus. I hope you enjoy.”

The scent of fresh falafel wafted out. True, I’d eaten falafel just a few hours ago, but my stomach growled because…well, more falafel. “Man, you’re the best. I can’t believe—Wait. You’re in the middle of a fast, and you brought me food? That seems wrong.”

“Just because I’m fasting doesn’t mean you can’t enjoy.” He clapped me on my shoulder. “You’ll be in my prayers. All of you.”

I knew he was sincere. Me, I was an atheist. I only prayed sarcastically to my own father for a better color of boat. Learning about the existence of Norse deities and the Nine Worlds had just made me more convinced that there was no grand divine plan. What kind of God would allow Zeus and Odin to run around in the same cosmos, both claiming to be the king of creation, smiting mortals with lightning bolts and giving motivational seminars?

But Amir was a man of faith. He and Samirah believed in something bigger, a cosmic force that actually cared about humans. I suppose it was kind of comforting to know Amir had my back in the prayer department, even if I doubted there was anybody at the other end of that line.

“Thanks, man.” I shook his hand one last time.

Amir turned to Sam. They stood a few feet apart, not touching. In all the years they’d known each other, they had never touched. I wondered if that was killing Amir even worse than the fasting.

I wasn’t much of a toucher myself, but every once in a while, a hug from somebody I cared about could go a long way. Caring about each other as much as Sam and Amir did, and not even being able to hold hands…I couldn’t imagine that.

“I love you,” Amir told her.

Samirah stumbled backward like she’d been hit in the face with a giant eagle egg. Alex propped her up.

“I…yes,” Sam squeaked. “Also. Too.”

Amir nodded. He turned and got into his car. A moment later, his taillights disappeared down Flagship Way.

Samirah smacked her own forehead. “Also? Too? I am such an idiot.”

Alex patted her arm. “I thought you were quite eloquent. Come on, sister. Your neon-yellow warship awaits.”

We undid the mooring lines, extended the mast, hoisted the sail, and did a bunch of other nautical stuff. Soon we were leaving Boston behind, sailing through the mouth of the channel between Logan Airport and the Seaport District.

I liked the Big Banana a lot more when it wasn’t bouncing through subterranean rapids or drifting toward inter-dimensional waterfalls. A strong wind filled the sail. The sunset turned the downtown skyline to red gold. The sea stretched ahead of us in silky sheets of blue, and for now, all I had to do was stand at the prow and enjoy the view.

After a long hard day, I might even have been able to relax, except I kept thinking about my Uncle Randolph. He had once sailed out of this same harbor, searching for the Sword of Summer. His family had never come back.

This is different, I told myself. We’ve got a well-trained crew of einherjar and the stubbornest, most devout Valkyrie in Valhalla.

Loki’s voice echoed through my head. Poor Sam and Alex. This quest will destroy them. They have no idea what they’ll be facing!

“Shut up,” I murmured.

“Sorry?”

I hadn’t realized Samirah was standing right next to me.

“Uh. Nothing. Well…not really nothing. I had a little visit from your dad.” I told her the details.

Samirah grimaced. “So the usual, then. Alex has been having visions and nightmares, too, pretty much daily.”

I scanned the deck, but Alex must have been below. “Really? He didn’t say anything about that to me.”

Samirah shrugged like That’s Alex.

“What about you?” I asked. “Any visions?”

She tilted her head. “No, which is interesting. Ramadan tends to focus the mind and strengthen the will. That could be why Loki hasn’t been inside my head. I’m hoping…”

She let the thought trail off, but I caught her meaning. She hoped her fasting might make it harder for Loki to control her. It seemed like a long shot to me. Then again, if my dad could make me do anything he wanted simply by commanding me, I would’ve been willing to try anything, even forgoing falafel sandwiches, to thwart him. Every time Sam said her father’s name, I heard the rage simmering inside her. She hated being under his power.

A passenger jet took off from Logan and roared overhead. From T.J.’s lookout at the top of the mast, he raised his arms and yelled, “WOOHOO!” as the wind ruffled through his dark curly hair.

Being from the 1860s, T.J. loved airplanes. I think they seemed more magical to him than dwarves, elves, or dragons.

I felt clanging and bumping below us—Alex and Mallory, probably, getting all our supplies stowed away. Halfborn Gunderson stood aft, leaning on the rudder and whistling “Fly Me to the Moon.” (

Stupid Valhalla elevator-music earworms.)

“Sam, you’ll be ready,” I said at last. “You’ll beat Loki this time.”

She turned to gaze at the sunset. I wondered if she was waiting for dusk, when she could eat and drink and, most important, curse again.

“The thing about that,” she said, “is I won’t know until I actually face Loki. Alex’s training is all about loosening me up, getting me more comfortable with shape-shifting, but…” She swallowed. “I don’t know that I want to be more comfortable with it. I’m not like Alex.”

That was undeniable.

When Sam had first told me about her shape-changing abilities, she’d explained that she hated to use them. She saw it as giving in to Loki, becoming more like her father.

Alex believed in claiming Loki’s power as his own. Sam saw her jotun heritage as poison that had to be expelled. She relied on discipline and structure: Pray more. Give up food and drink. Whatever it took. But shape-shifting, being fluid the way Alex and Loki were…that was alien to her, even though it was part of her blood.

“You’ll find a way,” I said. “A way that works for you.”

She studied my face, perhaps trying to gauge whether I believed what I was saying. “I appreciate that. But in the meantime, we have other things to worry about. Alex told me what happened at your uncle’s place.”

Despite the warm evening, I shivered. Thinking about wolves does that to me. “You have any thoughts about what my uncle’s notes meant? Mead? Bolverk?”

Sam shook her head. “We can ask Hearthstone and Blitzen when we pick them up. They’ve been traveling, doing a lot of—what did they call it?—long-range reconnaissance.”

That sounded impressive. Maybe they’d been networking with their contacts in Mimir’s strange interdimensional mafia, trying to find us the safest course through the seas of the Nine Worlds. But the image that kept coming to my mind was Blitzen shopping for new outfits while Hearthstone stood idly nearby, arranging runes into various spells to make time go faster.

I’d missed those guys.

“Where exactly are we meeting them?” I asked.

Sam pointed ahead. “Deer Island Lighthouse. They promised they’d be there at sunset today. Which is now.”

Dozens of islands dotted the coastline off Boston. I could never keep them all straight, but the lighthouse Sam was talking about was easy enough to distinguish—a squat building with a mast thing on top, jutting out of the waves like the conning tower of a concrete submarine.

As we got closer, I waited to spot the glinting chain mail waistcoat of a fashionable dwarf, or an elf in black waving a candy-striped scarf.

“I don’t see them,” I muttered. I glanced up at T.J. “Hey, you see anything?”

Our lookout seemed paralyzed. His mouth hung open, his eyes wide in an expression I’d never associated with Thomas Jefferson Jr.—pure terror.

Next to me, Sam made a strangled sound. She backed away from the prow and pointed to the water between us and the lighthouse.

In front of us, the sea had started to churn, swirling into a downward funnel like someone had pulled the bathtub plug out of Massachusetts Bay. Rising from the maelstrom were the giant watery forms of women—nine in all, each as large as our ship, with dresses of foam and ice, and blue-green faces contorted with rage.

I just had time to think: Percy didn’t cover this in basic seamanship.

Then the giant women fell on us like a vengeful tsunami, plunging our glorious yellow warship into the abyss.

HURTLING TO the bottom of the sea was bad enough.

I didn’t need the singing, too.

As our ship tumbled, free-falling through the eye of a saltwater cyclone, the nine giant maidens spiraled around us, weaving in and out of the tempest so they appeared to drown over and over again. Their faces contorted in anger and glee. Their long hair lashed us with icy spray. Each time they emerged, they wailed and shrieked, but it wasn’t just random noise. Their screams had a tonal quality, like a chorus of whale songs played through heavy feedback. I even caught snippets of lyrics: boiling mead…wave daughters…death for you! It reminded me of the first time Halfborn Gunderson played Norwegian black metal for me. After a few bars, it dawned on me…Oh, wait. That’s supposed to be music!

Sam and I locked arms on the rigging. T.J. straddled the top of the mast, screaming like he was riding the world’s most terrifying carousel pony. Halfborn