By four o’clock, we were standing in the creek bed, peering into the mouth of the tunnel.
Grover sniffed the air. “Cleanest river in the world?”
“This is after the Furies and snakes bathed in it,” I said.
“And who knows what else,” Annabeth added.
Grover dipped his shoe in the brown water. “I guess we can’t just roll the staff around in this muck and call it a day.”
I’d had the same thought, but I was glad Grover said it instead of me.
“We’ll have to go inside,” said Annabeth, distributing the flashlights. “Hope it’s cleaner upriver. Let’s hug the bank and try to stay out of the water.”
That was advice even I could recognize as wise. But staying out of the water proved hard to do.
As we forged ahead into the tunnel, the sides turned narrow and slippery. I found it impossible not to slosh around in the stream. My shoes didn’t start smoking, and my pants didn’t catch on fire, so I guessed the water wasn’t that toxic. Still, I added really hot shower to my to-do list, assuming I made it home that evening.
About a hundred yards in, Annabeth stopped. “Check it out,” she said.
She moved the beam of her flashlight across the tunnel’s ceiling, which was coated with moss and lichen so thick I couldn’t tell if there was man-made asphalt or natural rock underneath. Wherever Annabeth’s light passed, it left behind a streak of blue-green luminescence.
“Cool.” I used my flashlight to draw a glowing smiley face on the wall.
“How old are you?” Annabeth asked.
“Eight just last week.”
That got a smile. I loved making her smile when she was trying not to. It always felt like a victory.
We spent a few minutes painting light graffiti. Grover wrote Pan 4ever. I wrote AC+PJ. Annabeth traced concentric arcs until she’d made a blue-and-green rainbow. The moss kept glowing for quite a while, filling the tunnel with a cool turquoise light.
Up ahead, the channel widened into a much larger space. The sound of the current became louder and throatier. We stepped into a cavern so massive it seemed like a different world.
Under a cathedral-high ceiling covered with glowing stalactites, the river wound north between rolling plains of yellow grass. Ash-colored trees dotted the landscape, leafless and stunted, their branches curled like arthritic fingers. The scene reminded me of the Fields of Asphodel down in Hades’s realm—and the fact that I can make that comparison the same way you might say Oh, yeah, looks like Midtown is a really sad statement about my travel history.
Here and there, outcroppings of granite made islands in the grass, but the main attraction was the river itself. It wound lazily through the cavern, making big loops as if it were in no hurry to reach the daylight. Thick stands of reeds edged its banks. The current glimmered darkly in the blue moss light. The water did look cleaner here. The putrid smell was gone. But in a pool about twenty yards upstream, dozens of slithery, slimy whiplike creatures were rolling and writhing in the shallows, making me never want to eat spaghetti again.
“Gross,” Annabeth muttered.
“Hey, now, check your mammalian prejudices,” Grover whispered. “Reptiles are people, too.”
“With poison,” I said. “And cold blood. And a nasty bite. And . . . okay, maybe that also describes humans.”
Grover nodded. Thank you.
“Lights-out,” Annabeth whispered.
We switched off our flashlights, though the snakes didn’t seem to have noticed us yet. They were too busy frolicking and power-washing their scales.
I scanned the horizon. “You think we can sneak around them, go farther upstream?”
Grover sniffed the air. “This whole place smells like monsters. I can’t tell if there’s more besides the snakes nearby. Anything could hide in that tall grass.”
“Including us,” Annabeth said. “If we can’t fight the serpents, sneaking around them sounds like our best option.”
“Okay,” Grover agreed. “Let me go first, though. I might be able to pick out a safe trail through the fields.”
It used to be a rare day when Grover volunteered to go first through dangerous territory. I was too impressed to argue. Look at my old friend . . . taking charge and kicking grass. Sometimes I forgot he wasn’t a scared junior satyr protector anymore, but a scared Cloven Council elder. I guess we’d both grown up a lot.
At least here, Grover was in his element, assuming this creepy cave still counted as nature.
We waded through neck-high grass as sharp as hacksaw blades. Grover managed to navigate us around the thickest patches, but I winced every time a wisp of yellow snagged my arm. To make matters worse, the field crackled like bubble wrap as we walked through it. I imagined we’d be audible to any monsters hiding in the undergrowth.