Gaz led the way back to the annex entry. As Dib followed, he noticed the way Gaz kept her head low, eyes on the floor. She couldn't have been that jumpy about falling into holes, but Dib wasn't about to ask what her deal was. Gaz kept her shoulders so rigid, Dib thought spikes might pop out if he got too close, or said the wrong thing.

They exited the hall, sidled around a large hole, and were in the entryway proper.

"Called it," Gaz said.

Dib shifted a step to the right to see what his sister meant. "Zim?"

The alien lingered in the doorway opposite the one Dib and Gaz had come through, while GIR lovingly stroked the splintered wood frame. Zim glared at Dib, eyes shiny even in the dimness.

"Dib." Zim had that flat, barely-controlled tone. "Still alive, I see."

"Yeah." Dib stared at GIR; he looked like he'd used someone's corpse as a kiddie pool. "By the way, I gave your robot a little bag with a shriveled-up tongue in it. So did he lose it, or—"

Zim thrust a hand forward with an unamused expression. The tongue bag dangled by his pinched fingertips. Dib smothered the urge to point out the irony of Zim holding the item like it was a creepy bug.

"GIR claimed we need it," Zim said. "Explain."

"Okay, but how are you carrying that without getting hit with some kind of horrible ghost-vision curse?"

Dib pointed at the drawstring bag, and Zim gave it a sideways glance. "Oh, it was probably the power stone I used to clean all the whiny, screamy dead humans out of GIR's head."

GIR scraped a walleyed piggy in the floorboards with one metal finger. "It's all quiet now. I wish they'd return my calls."

"No, you don't." Zim approached Dib in several brisk steps and held it out. "I sacrificed a powerful alien artifact for this disgusting thing. You're welcome." Dib took it, and Zim backed up a few steps. "Now tell me."

Dib held his breath for a moment, expecting something bad to happen. Zim fixing him with an expectant look, Gaz crossing her arms with her hands tucked into her hoodie sleeves, and GIR adding devil horns to his pig drawing all stayed the same.

"There's an escape charm," Dib said, slipping the bag gingerly into a trench coat pocket. "We're supposed to put our paper scraps together, and redo the ritual."

Zim's eyes widened. "Really? That's it?" He crammed his right hand up the cuff of his left glove, digging for something. "Then what in unholy filth are we waiting for?!"

"We can't yet," Dib said, and Zim stopped. "First, we have to do the ritual different to get out, and I don't know what the difference is." He glanced at Gaz. "Second, I think we have to appease one of the ghosts."

Zim grit his teeth and clenched his fists, looking ready to launch into a conniption fit, then relaxed with, "Wait. Do you mean the wretched little murder-girl? That—Sachiko?"

Dib blinked. "Yeah. How'd you know?"

"Because I told him," Gaz said. "I figured we'd either have to deal with her or the nurse to get out. But we have her tongue now, so..."

"Yeah, that makes sense. Now we just have to find the body, which I think is in the basement." Dib eyed the dark lines between the floorboards. "If there even is one, because I haven't found a way down yet."

"If you're implying that we have to go back and search every inch of this school..." Zim's voice was a restrained growl, but his antennae were pressed flat against his skull. He trailed off without coming up with a threat.

Then Dib remembered. "Oh, right." He reached into his inside pocket and pulled out the tiny key. "I got this from that suicide-looping principal. I bet it goes to his office." He looked from Zim to Gaz. "Either of you come across a locked door?"

Gaz shook her head. "Just lots of fake ones."

Zim kept quiet, glaring at the giant robot GIR's piggy drawing now included. Then his antennae twitched up like raised eyebrows.

"There was one," Zim said. "It rattled, but it wouldn't open."

Dib stowed the key back in his pocket. "Where is it?"

Zim hoisted GIR up by the robot's non-bloody hand, just as he finished drawing a girl pig with sexy legs on the shoulder of his demon-horned piggy's death mech. "Upstairs. Follow Zim to victory!"

Zim hurried through the doorway he and GIR had come out of, and Gaz followed suit. Dib brought up the rear, patting his pockets to make sure the necessary items were in place.

Dib watched Zim as he led them to the dark stairwell. The alien kept a tight hold on his robot's hand.

The key, which looked like it belonged to a diary instead of a door, fit perfectly and unlocked the principal's office. The instant it opened, GIR yanked out of Zim's grasp to rush into the room.

"Hey!" Zim dashed into the office after him, and stopped dead three steps from the doorway. He hugged his spindly arms, hissing in his breath, and backed up, hunching into himself.

Dib stayed just behind the threshold. "What? What is it?" Zim didn't respond. He retreated another step, bumped into Dib, and spun to face him, eyes wide.

Dib peered into the room; GIR had attached himself mouth-first to one of the armchairs set out for visitors. He looked down at Zim. "What is wrong with you?"

"You don't hear it?" Zim's voice was thready. Dib nudged him aside and stepped into the room.

It's her fault.

Dib froze. It was the voice from the tongue vision.

I didn't mean for it to happen. She overreacted! I didn't intend to...

Gaz shouldered past him, and Dib sucked in a deep breath—he didn't realize he'd been holding it. He shook his head and looked around, hair prickling from the office's supernatural chill. Charms littered the walls, particularly on one side of the room.

It's her fault. I didn't mean for it to happen.

Principal Yanagihori's disembodied voice continued muttering from all directions. Gaz clenched and unclenched her hands throughout every excuse. Giving his sister a slight berth, Dib headed for the desk at the front of the room.

She overreacted!

Small booted footsteps tapped across the floor behind Dib as Zim braved the room's concentrated entitlement to stay close to his robot. GIR made cartoony chewing noises on the armchair upholstery.

I didn't intend...

Dib found a hole in the wall behind the desk, square and big enough to crawl through. Horizontal scrapes marred the floor in front of it, stopping at one cabinet standing flush with another.

He got on his knees, took a bracing breath, and felt into the hole. His fingers brushed cold metal, and he jerked away. When nothing jumped up to rip his arm off, he reached down again. It was the top rung of a ladder.

Dib straightened up and turned to the others. "I found the way down."

Gaz looked up from the floor. She blinked several times, as if coming out of a trance, and came forward.

Dib carefully lowered himself into the hole, finding a foothold a few rungs down. He went down, then stopped when his chin was level with the office floor. He had a clear view of Zim trying to tear his robot off the armchair.

"We're leaving!" Dib called out, and ducked below the hole.

"No!"

Frantic scuffling and fabric ripping came from the office above as Dib descended.

The underground tunnel system was better lit than the school above. The electricity somehow still functioned, even if the hanging bulbs contrasted with the rock walls and uneven wood supports.

Dib stepped off the ladder, warm humidity replacing the cold from the principal's office. The tunnels were unmarked as far as he could see, but he caught a faint stench of something from further in.

Gaz descended next, followed by Zim, who skipped the ladder in favor of spidering down on his Pak legs in two seconds. He grimaced and made shooing motions at GIR, who was clinging to the back of his head. The robot jumped to the floor, and Zim hastily brushed away the dried blood that had flaked off GIR's body.

As Dib led the group further in, the insulating nature of the tunnels produced a new kind of oppressiveness the school above didn't have. The creaking wood, crinkling glass, and papers shifting on the wall were all behind them, leaving only footsteps muffled by solid earth. Dib wasn't claustrophobic when he stepped off the ladder, but the narrow halls, low ceiling, and Zim staying less than a foot behind made him feel like a textbook case.

Playful laughter encircled them, and Dib stopped. Zim screamed, bumped into Dib from behind, and screamed again.

Dib spun around. "Would you stop that?!"

Zim clutched GIR to his chest, heedless of the sticky red dye job. "It's her! She found us!"

Another girlish giggle echoed off the walls. Dib sighed, faced forward, and continued walking. "She's buried here, Zim. Of course she's going to have more of a presence. Just deal with it."

Zim made a small noise in the back of his throat. Dib didn't hear GIR's feet return to the floor.

After a few turns, the tunnel opened up into a room. Shelves lined with human heads of varying freshness broke up the subterranean monotony.

"An underground mausoleum," Dib muttered, locking his gaze on the floor. "Great."

He hurried past the shelves, empty eyes and sockets alike staring from his peripheral vision. He didn't count how many shelf rows there were—only that they were all full, and that meant too many.

Someone was breathing heavy when they exited the head room, but Sachiko's laughter echoed from behind, and Dib didn't want to stop to check. He figured it was him, anyway.

A dead end loomed ahead, with a doorway to the right as the sole option. The faint smell from the start of the tunnel was now strong enough that Dib had started taking shallower breaths.

"I'm not going in there." Zim's voice came from several feet away, and Dib turned to see him standing close to the wall. GIR was by his side, picking at the rocks. "And neither will you, if you haven't completely lost your idiot Earth-mind."

Dib huffed. "I'm not excited about the return of rotten meat potpourri either, but Sachiko's body could be in here."

He went for the doorway again, and Zim screeched, "Listen to me, you stupid—"

A huge grey figure materialized from the darkness beyond the doorway. Dib registered the red eyes, oil-slick tearstains, and raised sledgehammer an instant before it fell.

Someone rammed Dib into the wall beside the doorway, and the hammer struck stone. It must have been Gaz, Dib figured, because Zim was already Pak-spidering away in a shiny metal blur with GIR in tow.

Dib shoved himself away from the wall and staggered into a full sprint. The nondescript walls blended together, until another doorway came into view. He grabbed the side and swung himself into the room.

He stood inside it for a few seconds, heartbeat too loud in his ears to listen for thundering footsteps and guttural roars. The room smelled wet and terrible, which made catching his breath excruciating.

His mind flashed images of the grey zombie filling the doorway, and Dib stumbled forward in the poorly lit room. He tripped on something, which gave under his foot with a meaty squelch as he fell face-first into a stinking pool.

Dib yanked his face out of the shallow water, coughing and spitting out the coppery coating inside his mouth. The pool lapped around his elbows as he pushed himself up. Even with the bad lighting, its color was off.

Something bobbed in the disturbed liquid, and bumped into his arm. Dib looked at it, straight into the eyeless sockets of a teenage schoolgirl.

Dib stopped breathing. Eyeballs—too many to just be hers—floated in the reeking human stew, along with hanks of hair, globs of flesh, and bodies in every stage of decomposition. That water had been in his mouth.

He almost fell beneath the surface again in his haste to get out of the corpse pool, and collapsed on his hands and knees to vomit on the ground. The image of those dark eye sockets burned a hole in his mind as reddish-brown blood-water dripped down the inside of his glasses.

Dib rose on shaky legs and lurched for the doorway. It wasn't until he was out in the tunnel lighting that he remembered why he'd entered that room in the first place. He whipped his gaze up and down the corridor, listening hard.

All he heard was a low, pulsing hum from deep inside his head. It had started after he entered the annex, and now more pain came with each pulse.

It felt like a countdown.

As Gaz fled, she didn't notice Dib had gone in a different direction. She also didn't notice the tunnels going dark around her.

A form of consciousness returned in sluggish flickers, a drugged haze. She was shuffling down a narrow corridor with jerky, uncoordinated movements.

Twin cyan circles shined out of the gloom. They belonged to some idiot robot, just standing there, staring at her. Gaz reached for them, and the lights shrank into the infinite distance.

Gaz slid her eyes away from the far-off robot, dream-like, to observe her outstretched hand. It was pitch black.