I tried to imagine my dad, uncredited inventor of the Excalibur Calculator Pocket and lawn-mower-for-hire, down here among the trolls. But I could only imagine him rolled into a ball in the corner. Nonetheless, Dad had been right about one thing: Uncle Jack might be the bravest kid who ever lived.

“Translate, Jim, translate,” Tub hissed.

“No time,” I murmured. “This one talks a ton.”

“Oh, okay. I’ll just keep on being completely terrified, then.”

“Nothing so drowns me in melancholic murk as does Jack’s uneasy fate,” Blinky continued. “Yet I rouse myself from that lachrymose lugubriosity by recalling the forty-five years of peace that followed. The hundreds of human children whose lives were saved. Your uncle is responsible for that, with the humble assistance of present company. Jack Sturges brought an end to what you call the Milk Carton Epidemic.”

“Why did it happen? Who took all those kids?”

Blinky’s eyes grew redder. Half blind though they were, every one of them found me.

“Gunmar the Black.”

ARRRGH!!! howled. Lamps flickered. Stones spilled from the sides of the tunnel.

“An apropos reaction from my shaggy sidekick! Jack helped us vanquish Gunmar the Black—alias the Hungry One, alias He Who Sups of Blood, alias the Untangler of Entrails—thereby draining Gunmar of his considerable power. Now, for reasons we do not yet understand, Gunmar is once more growing stronger. It has always been his goal to invade the human world and feast at will, and that is precisely what will happen if we do not locate him soon.”

The tunnel darkened as we passed through a stone portico opening into a spacious cavern. Once my eyes adjusted to the brighter light I recognized it as the place I’d been before. There was the steaming stove and the mountain of old bicycles lording over the various other foothills of junk. Above, the packets of hot-wired fluorescent lights spat irritably and radiated sickly glows.

“Oh, neat,” Tub said. “Can I have one of these bikes?”

He reached out and I slapped his wrist.

“Dead kid bikes!” I hissed.

Tub scrubbed at his hand as if he’d plunged it into a bowl of spiders.

Across the cave, Jack was standing before a large, flat stone and sifting through a pile of sharp metal that glinted in the firelight. I found that I didn’t especially want to know what he was doing. Instead, I turned back to the trolls.

“This Gunmar guy,” I said. “How do you know for sure he’s getting stronger?”