“You look ridiculous,” Alex said to Ren.

They had just dropped through a drain in the floor of the Met’s subbasement and were in an old sewer tunnel. Ren had rubber boots on her feet, a mask on her face, and a white plastic suit everywhere else. The suit was way too big for her, so the sleeves and legs were bunched up with thick rubber bands. All of the gear had come from Todtman, courtesy of a trip to the Home Depot on Fifty-Ninth.

“I guess sewer suits don’t come in petite sizes,” she said, swinging a large flashlight back and forth in front of her. The beam lit a stream of dark, soup-thick water passing by below them. The masks were designed to filter out things like fiberglass insulation and cement dust, but did little for the smell.

“I think these suits are supposed to be for painting,” said Alex.

“This place could use a good paint job,” said Ren as she swung her flashlight across the moldy, filth-caked top of the old sewer tunnel.

“How did you know this connected to the museum, anyway?” said Alex.

“My dad mentioned it once: ‘drainage subbasement.’ I’d been thinking about how the two of them managed to just disappear. How could the Stung Man have outrun Todtman? Plus there were guards at all the exits, because of the blackout. They couldn’t just magically disappear — I think — so, where could they have gone?” She swung her flashlight around again. “No guards here.”

Alex managed a nervous laugh. He was at least as scared as he was grossed out, and the chatter helped. Remember why you’re here, he told himself. Remember the mission. If Al-Dab’u and the Stung Man really exited this way, then they needed to figure out where they went. He fingered his amulet to calm his nerves a little.

Ren was holding her flashlight in her left hand and wielding a small crowbar in her right. He wasn’t sure how much good that would do …

Alex swept his flashlight in front of him and tried to find a clear spot to put his foot down. They were walking along a thin ledge, just above the slow-flowing sludge. He stopped for a moment to check their printout of the Upper East Side sewer system with the flashlight.

“We are totally doing Todtman’s dirty work,” said Ren.

“I’m not sure I’d want to be him at the museum today, either,” said Alex.

“This is still tougher,” said Ren, stomping her boot down in the muck to make her point. “Not many people could do this.”

Alex didn’t disagree with either statement, but he didn’t really see where she was going with it. “Okay,” he said.

“Like, do you think Jesse could do this?”

“Jesse Blatz?”

“Yeah, just for example.”

“You need to get over that kid. You’re just as smart as him.”

“I’m maybe sixty percent as smart as him,” she said and whacked at the air with her crowbar. “Just answer the question.”

“Do I think he could do this?”

“Yeah.”

“Walk through toilet water? Probably.”

“I don’t mean that. I mean, I don’t know, get chased by a mummy and then chase it back.”

“Then, no. I don’t think he could do this.”

Ren’s white mask bobbed up and down in an emphatic nod. “I don’t, either.”

Alex took a few more steps through the turgid muck. “He’s too smart to.”

They both chuckled. It echoed slightly in the tunnel and they nervously swung their flashlights from side to side in the darkness.

The ledge narrowed and Alex gave up on it and stepped off so he was up to his ankles in a slowly flowing, stew-thick stream. They trudged on quietly for a while. It was quiet except for the squelching of their feet. It was horrible down here, but it was just the two of them — at least he hoped it was. He felt like he could say anything. And hadn’t Ren just done that?

“Hey, Ren?”

“Yeah?”

“Do you think this …” He took a few more steps. “Never mind.”

“What?”

“Okay. Well. Do you think this is all my fault?”

“No way! Don’t be dumb,” she said — and then very quickly changed the subject. “Anyway, we have to concentrate. Keep your eyes open.”

“What exactly are we looking for? It’s not like they would’ve left footprints.”

This time he stomped his foot to make his point.

“Look for scraps of cloth,” said Ren. “That thing’s, like, mummy garb didn’t look too secure.”

Alex stopped to check the sewer map again and something solid bumped into his boot. He swung his flashlight around, but whatever it was had already drifted downstream. A few minutes later, something else floated by. This time, he got his flashlight on it. It was a dead rat. “Gross,” he said.

“I saw one of those, too,” Ren called from up on the ledge.

After another ten minutes of trudging straight ahead, they came to a T-shaped junction in the pipes. Alex located it on the map. “Which way?” he said.

Both passages smelled terrible. They swept their flashlights in one direction: nothing. Then the other: “Is that another rat?” said Ren.

It was. And this one was up out of the water, lying dead on its side on the narrow walking ledge. Ren headed toward it.

“I guess we’re going this way,” said Alex, following along.

Ren bent down over the dead rodent, and Alex leaned over her shoulder for a look. “Does it seem weird that we haven’t seen any live rats down here?” he said.

“I think I know why,” said Ren, holding her flashlight closer to the carcass. “See that?”

Alex saw. “It’s a sting.”

“Well,” said Ren, “not exactly a footprint, but …”

They followed the trail of dead rats for what felt like five miles — and smelled like fifty. Every movement and every sound made them jump. It wasn’t just the certainty of dead rats and the possibility of live scorpions that had them on edge. They were alone, in the dark. And the Stung Man could be anywhere.

Todtman was sure he would be long gone, that the sewer was “a route and not a destination.” But Todtman wasn’t there.

As Alex walked, he frequently had to stoop down to avoid bumping his head. Ren, not so much. Finally, the passage began to slope slightly upward. The floors got drier and pipes ceased to pour filth in on them. There were even occasional slivers of daylight filtering in from above. It all came to a dead end at a battered concrete wall.

Alex smacked the wall. He’d been so sure they were going to find something.

They hadn’t seen a dead rat for a while now and seemed to have run out of leads. Alex checked the map again. “I think maybe we’re near Lexington Avenue,” he said.

Ren inched her flashlight beam slowly across the concrete, and that’s when they saw it: a dark, narrow gash that didn’t catch the light. There was a vertical gap in the wall.

Alex walked over to it, took a deep breath, and ducked his head through.

“See anything?” said Ren.

“It looks like another tunnel, but it’s too dark to tell.”

He stood still.

“Wait … I think I feel something.”

“I feel it, too,” confirmed Ren. “It’s getting stronger.”

It started as a faint rumbling — just a tickle in the soles of Alex’s boots — but it quickly grew strong enough to rattle his teeth. For a few seconds, Alex was afraid it was an earthquake. I do NOT want to die down here, he thought. Then he saw a bright round light in the distance and yanked his head back through the gap as it approached.

He had to shout to be heard over the noise: “It’s the subway!”

The rumbling reached a crescendo as the train whipped by on the other side. They could see the lights and hear the wind from the subway cars.

As soon as it passed by, Ren rushed forward and stuck her head through the gap. It was wide enough that she could have squeezed through it if she wanted.

“What was it?” asked Alex.

She pulled her head back in: “The 4 train. Downtown express. We’re under Lexington Avenue!”

Alex felt like hitting the wall again — maybe punching it this time. “If they got into the subway tunnels, they could be anywhere now.”

Ren kept quiet. She didn’t have an answer to that.

They had to trudge back through the sewer, back through dead rats and unspeakably gross sludge, to get to the closest manhole. They marched together in silence. Ren coughed because of the smell every once in a while, and Alex’s mind was on his mother. Eventually, they spotted the narrow steel rungs of the little ladder. Alex went up first with the crowbar. It was the first time he’d really tested his new strength.

His muscles began burning almost immediately, unaccustomed to the effort. He wanted to take a break, but didn’t want Ren to see him fail. He put all his weight into one big push, and the heavy lid finally popped loose.

Timing the traffic was tougher, and Alex was too impatient to wait. He’d been down there long enough. He listened for the first break in traffic and then muscled the manhole cover aside.

“Wait!” called Ren, a few rungs below.

Alex popped his head out to look and a taxi nearly whack-a-moled him. He ducked down and reached up to see if his head was still there. He tried again: all clear. He scrambled up the little ladder, then stood there with his hand out in a stop sign.

There was only so official a twelve-year-old was going to look in late-afternoon traffic, but the suit and mask helped. Ren scrambled up after him, then they pushed and kicked the lid back in place and sprinted to the curb. A sidewalk full of shoppers stared at them. They were so relieved to be back in the daylight that they barely noticed.

“Gas leak,” said Ren matter-of-factly. “Everything’s okay now, though.”

They hurried around the corner and peeled off their filth-splattered plastic suits. Ren took the opportunity to scold Alex about the taxi. “You took a lot of dumb chances back there,” she said. “Wading through that sludge — what if you’d stepped on something sharp? And you almost lost your head rushing into traffic.”

Alex shrugged. He was done with being careful about every little move. He took out his phone. “We think they went into the subway tunnels,” he said when Todtman picked up. “Because that’s where the trail leads. And also because we really, really don’t want to go back into the sewer.”

Alex’s aunt and uncle still weren’t home when he got back to the apartment that evening. The door to Luke’s room was open, and Alex ducked his head in. The walls were covered in posters. Alex was expecting football and baseball, but what he saw was mostly track and a lot of Olympic rings. Luke was on a mat on the floor doing yoga. Alex decided not to comment. Because: muscles. “Olympics, huh?” he said instead.

“That’s the plan,” said Luke, continuing to stare at the ceiling, as the pose required.

“What, like, event?” Alex was in shaky territory here. There were only a few events he really knew about.

“Decathlon.”

Alex did, however, speak more ancient Greek than most kids. “That means ten — ten events?”

Luke changed positions. If Alex had to give this one a name, he’d call it Improbable Crab pose. “Yeah, ten events,” said Luke, “but I got a strategy. If I get really good at one of them, I can just switch and concentrate on that. It’s called specialization.”

Luke pronounced the word like it was a fancy French dessert.

“That’s a lot of work,” said Alex.

“I like the work,” said Luke, his muscles beginning to tremble with the strain of the pose. “Problem is it’s expensive. Camps, coaches, travel. ’Rents kind of aren’t having it.” Luke collapsed onto the mat and wiped the sweat from his face with his forearm. He looked over and flashed a quick, unhappy smile. “Say I should just play football.”

Alex gave him his best I hear ya, man headshake, but what he was really thinking about was his struggle with the manhole cover and how he still got winded so quickly. “Hey, Luke,” he said, “think you could show me some of those poses sometime?”

“Sure thing, little man,” he said. Alex wished he wouldn’t call him that. Luke was a good six inches taller than him but only a year and a half older.

Alex knew he needed to shower — and probably shower again — but he was eager to get back to his little room. He needed to practice with the amulet. He told himself that even if they hadn’t found the Stung Man today, they would eventually. That would mean another confrontation — on enemy turf this time.

He closed his door and poured a small bag of glass marbles out onto the desk. He had to start somewhere, and he heard Todtman’s words from that first night: “All of them can do certain things. Move small objects, and so on.”

It took him a while, but soon he could roll a marble across the desk and back again. Even after all he’d seen, it was still amazing to feel his pulse rev and see the little blue orb start to roll on its own, and then to change directions. His whole life he could barely move his own body — now he could do things even Luke’s Olympians couldn’t.

He grasped the amulet tighter and tried for two at once. For a second it worked, but then a small crack appeared in the second one and — prakk! — it fractured all the way through. Alex looked back at the first one, still clutching the amulet tightly. It shot straight forward, pinged against the wall, and dropped down behind the desk.

The marbles weren’t the only casualty. He released the amulet and shook out his hand. The wings had pressed deep crescents into his skin, and now his head hurt. He put the remaining marbles back in the bag.

His head cleared after dinner, and he practiced some more. He couldn’t quite open and close the window, but he could lock and unlock it. He was getting better, but before long his headache was back. Is it worse this time? he wondered as he went to the bathroom to look for aspirin. He reached for the handle of the medicine cabinet.

He missed.

He squinted at the little handle.

He saw two of them.

It was worse. Definitely worse.

He took three aspirin. He saw six.

Before bed, he decided to use the scarab for one more thing. He wanted to feel that electric quickening one more time. And the urge to see if he could set the alarm clock was irresistible.

Why didn’t Mom tell me about this? he wondered as he stared at the little buttons. He’d been picking at the question like a scab. He couldn’t let it go. She wore it every day, so why did she leave it behind? He managed to change the hour and was working on the minutes when he was blindsided by a new possibility: Did she know she wasn’t coming back? An ugly spatter of words snuck up on him, as if whispered into his ear: He needs to feed. There was a thick crunch from the alarm clock and the numbers blinked out.