“Are you okay?” Leo asked. “I’ve been really worried about you.”
“You’ve been worried about me for a change?” Shelly laughed. “I’m more than okay. Roger’s found the antidote!”
“I guess so!” Leo said, grinning with relief. Not only was Shelly back to being human, but she also seemed cool about the half-zombie he kept hidden in a secret lab behind the back wall of his closet.
“Roger is simply a genius,” Shelly said, wrapping her arms around him. Roger coughed a little, and his face turned greenish pink. “I can’t believe you’ve been keeping him from me all this time.” She squeezed Roger, and green pus oozed out of his left ear.
“I’ve been learning how Roger saved my life.” Shelly turned the laptop around to show Chad and Leo a Web site called The Nordic Museum of Zombie Folklore and Fact. “Nordic refers to people who lived in northern Europe a thousand years ago,” Shelly explained. She scrolled down to a section titled “The Outbreak of 982.”
She read aloud: “For many years, experts have disagreed on this important event in zombie history. Is it just a myth, or did it really take place? Nordic records tell a spellbinding tale of zombie-like creatures walking the earth. The creatures are mysteriously returned to human form. The Torr Tapestry—”
“That’s a rug with pictures on it, right?” Chad asked. He and Leo were both fully awake now.
Shelly nodded. “The Torr Tapestry tells the story in vivid pictures. Most interesting are the middle panels, which feature a curiously bright green plant. Experts have now identified this plant as the Gloria viridis, or green glory. Nordic peoples believed it held magical powers. Sadly, this fascinating plant is now almost extinct.”
“That’s it! That’s the plant from Principal V’s office! The green glory!” Leo shouted.
“It is, my friend! And look closely at this picture in the tapestry.” Roger clicked to another page. Chad and Leo peered at the screen.
“That’s our plant all right,” Leo said. “But it seems to be covered in some kind of unripe berry or—” Leo squinted.
“They’re slugs,” Shelly said, “matching green slugs!”
Camouflage. The word popped into Leo’s brain. The slugs were the same color as the plant because the slugs lived on the plant. They hid from predators by blending in with the plant’s leaves.
Roger flinched as Shelly patted him on the back. “Rogie over here studied the entire tapestry for hours. He noticed that some pictures showed the green glory with slugs, and some showed the green glory without slugs. In the slug-off pictures, the people looked like zombies. In the slug-on pictures, they were human. And that’s because the slug—”
“—is a parasite!” Leo finished. Answers were flashing like neon signs in his brain now. The slug lived off the plant. It didn’t eat the plant’s leaves—none of the leaves on the sample were chewed. It ate the green dust, the dust with Z. coli, the zombifier.
“Even more,” Shelly was still going. “The slug gives off tons of mucus, or slime. That’s why Roger first confused it with the North American Mucinus maximus.” She pointed to the bright green slug. It was now in a jar with Principal V’s plant instead of Roger’s finger. “Of course, that’s totally understandable. But the slime of this slug—the European Mucinus sanitas—is a powerful antidote to Z. coli. That was Roger’s theory, and—” She held out her arms and twirled around. “I’m living proof that he was right.”
“Whoa.” Chad was resting his chin thoughtfully on one hand. “So let me get this straight. Principal V gets his hands on this rare European plant. He takes all the slugs off it, cuz they eat the zombifier in the plant’s dust. He uses the dust to turn the whole school into zombie slaves. And now we need to cure everybody with the slug’s magical slime?”
“Something like that.” Shelly picked at a fingernail.
“Um, do we have any more slugs?” Chad asked.
“Sadly, no,” Shelly said. “We’re guessing Principal V got rid of the slugs. Except for one, obviously, which escaped.”
“And I found,” said Leo, “when I was swimming in gym last week. It had crawled under my green towel, probably looking for a habitat.”
“I’ve got a plan! I’ve got it! Ding, ding, ding!” Shelly shot up and started dancing around like a game show contestant. “Notebook please, Leo!”
Shelly turned to a fresh page and outlined her idea in neat handwriting. Even Leo had to admit it was workable. And it got him to come up with a few good ideas of his own. After several minutes and just a few cross-outs, Leo and Shelly had done it. They’d mapped out a plan to save their whole school from zombiehood using just one slug.