The warm Florida wind battered Zack’s face as his speed multiplied by the force of gravity per second. Eight Mississippi. A squeal from Twinkles blended with the air whooshing past their falling bodies. Nine Mississippi.

Out of the corner of his eye, Zack could see Rice Superman-ing through the open sky like a pro, then in a blink he lost sight of his friend. Ten Mississippi. Zack yanked the cord like Ozzie had told them, and the parachute discharged skyward, catching the breeze with a jolt.

Zack and Twinkles floated over the Florida peninsula. A bird’s-eye view of Fun World appeared beneath them as if they had been dropped into a board game come to life.

But it wasn’t a game. And Zack knew it. This was a matter of life and eternal zombification: the living versus the undead. One misstep and humanity would be history.

He zoomed over the zombie hot zone and landed feet first with a clang on a bed of chain-link. The parachute came down over his head and tinted everything red.

“Whoa!” Zack was looking down from fifteen feet in the air onto a complex of state-of-the-art batting cages. He tugged the parachute’s tent away from him and scoped the amusement park.

From where Zack had landed atop the batting cages, Fun World forked off into three multicolored cobblestone pathways with palm trees and gumball machines lining the sides. Huge twisting roller coasters soared across the sky. A red-white-and-blue monorail system weaved its way around to the different sections. This place would have been perfect except for the sluggish, foot-dragging swarms hobbling beneath him.

Hundreds of undead freaks meandered through the park. Their baleful wails of brain-craving desperation permeated the hot tropical air.

Zack looked over his shoulder to check on Twinkles.

The little pup was just fine. His tongue hung from his mouth as he panted. “Ruff!”

“Come on, Twinkles,” he said to the pup. “We gotta get down from here.”

Zack detached the parachute from the shoulder straps and then took off the sweatshirt he was wearing. He pulled the drawstrings of the hood tightly together and knotted them. Then he placed Twinkles in the sweatshirt and tied the sleeves together, and slung it over his shoulder like a knapsack.

With Twinkles secure, Zack began to crawl backward down the giant fence backstop. Halfway to the bottom he looked down. The zombies were on their way, staring up at him, snorting and salivating. He knew he had to bail now or else they’d get him for sure. He took one more step down the chain-link and then dropped the rest of the way. As he landed on the pavement his left leg buckled in such a way that he was fairly certain his knee was never going to be the same ever again. But he had to keep moving.

As soon as Zack caught his footing, an acne-faced, teenage zombie freak lurched right in front of him. The teen’s nose was ripe and clammy and looked like a steamed pork dumpling. Its body reeked as though it had been sprayed recently by a skunk.

Zack dodged around the undead stinker, gagging and coughing, then dashed into the high-tech batting cages. He grabbed a baseball bat leaning in the corner. It had been a while since he’d held one. The cold, hard aluminum felt good in his hands. Zack looked at the zombie coming his way. “You’re in trouble, son.” He whirled around and popped the subhuman zombie stink bomb in the gut. Then he brought the bat up under the ghoul’s chin with a crunchy splat.

“Clickity-clap-clackow!”

Zack swung away from the fallen ghoul, bat at the ready. The zombies were converging upon him, his back against the fence. Zack ran over to one of the many gumball machines that the park was famous for. Tied to the candy machine’s metal foot, a large zombified rottweiler growled and slobbered rabidly. It had on one of those plastic lampshade collars around its head. Twinkles yapped at the zombie dog.

Zack hauled off and shattered the glass sphere containing the gumballs with the butt end of the bat. Bucket loads of gumballs spilled onto the sloped pavement, and the gathering swarm of zombies started to slip and stumble.

He shouldered his way past the shuffling ghouls and found himself at a fork in the road. The zombified moans howled all around him. He had to be careful, but he wasn’t scared. Fighting off zombies was one of the few things he was actually good at. Zack did a quick eenie-meenie-miney-moe then went for the center path that led into the middle of the theme park. He ran ahead in search of the others with Twinkles in the crook of his arm, doing his best not to be noticed by the zombies meandering around every corner.

Before long, Zack caught a glimpse of two familiar-looking figures up ahead. Rice and Ozzie were leaning over the control panel for a ride called The Viper—a mean-looking black-and-green roller coaster with two consecutive upside-down loops in the track. Zack waited for a pack of four zombies to go by: two undead parents with their rezombified offspring attached to child leashes. Zack crept behind the zombies as they passed and approached the Viper ride.

A huge sign for the roller coaster hung over the entrance to the waiting line with a creepy picture painted on it of a viper consuming its own tail.

“Guys, what the heck are you doing?” Zack yelled, skipping over a puddle of zombie sludge underneath the sign. “Where are Zoe and Madison?”

“We’re going to ride this roller coaster and get a bird’s-eye view of the place,” Ozzie said without missing a beat. “Hopefully we can spot them from up there.”

“Exactly,” said Rice. “We’re probably going to have to ride it a few times to get a good layout of the park.”

“Come on,” Zack said. “We have to find the girls and Olivia to see if she can even help with the antidote.”

“Zack,” Rice said seriously. “Get on the roller coaster.”

“No way, man,” said Zack. “I love roller coasters just as much as the next guy, but we can’t just leave my sister out there in the—”

“Dude,” Ozzie cut Zack off. “Get on the roller coaster.” His voice was stern and serious. The zombified moans were still howling all around them. Zack spun in the opposite direction and gazed upon the high-density zombie swarm converging on the platform. The flesh-guzzling mutants had grappled over the metal maze that designated the waiting line and they seemed impatient.

“You know how to work this thing?” Zack asked as he watched Ozzie fiddle with the controls.

“Think so,” Ozzie said.

“You think so?”

“Let’s do it, Oz,” Rice said, hopping into one of the roller coaster cars and pulling the padded restraints down over his shoulders, locking himself in place.

Ozzie hit a combination of switches as the zombies stumbled onto the platform, climbing over and crawling under the metal handrails like a jungle gym. The roller coaster started to move forward slowly, and Zack and Ozzie jogged alongside, hopping onto the ride.

“Arf!” Twinkles barked, squirming out of Zack’s lap, totally spooked by the ride.

“Twinkles, come back!” Zack shouted, grabbing for the pup, but he had already pulled down his mechanical restraint and locked it into place. Twinkles trotted quickly through the maze of shuffling zombie feet and raced down a wooden staircase at the back of the platform.

“Twinkles!”