Madison Miller lay on the beach, clutching her arm, speaking some kind of mean-girl gibberish. She sat up and slipped the pink parka off her shoulder, and pulled up the sleeve of the hooded sweatshirt that she was wearing underneath. The zombie virus had spread darkly through the veins around her bite wound.

Rice produced an Ace bandage from his backpack and started wrapping Madison’s forearm.

Madison gritted her teeth and gulped back her tears. “It stings!” She groaned and stamped her foot. “Did we find Twinkles?”

“Umm.” Zack panicked. “Yeah, uh—he’s fine.”

“Don’t lie to her, Zack,” Zoe said. “Not on her undeathbed.”

“He’s gone?” Madison screeched, and tears streamed down her cheeks.

“It’s okay, Madison,” Rice said. “We’re gonna find the little guy.”

“Promise?” she asked, and let out a small pathetic cough.

“Yep,” Rice said with resolution and his fingers crossed behind his back. “Just relax.”

“Ugh, I don’t feel so good,” she said. Madison held up her smartphone in front of her face, using the camera like a mirror.

“Fair warning.” Zoe crouched down beside her BFF. “You’re not looking so good either.” Madison scowled at Zoe then gazed at the touch screen and watched her pale skin begin to wither slightly. Dark bags hung under her eyes, and her cheeks began to droop, making her face look jowly, like an old man’s. Madison’s lips quivered as she breathed heavily through her nostrils. She threw the phone on the ground and squealed disgustedly. “This is so not cool.”

“Don’t worry, Madison,” Zack told her. “Once we reach Olivia, we’ll get you back to normal like that.” Zack snapped his fingers.

“Yippee!” Madison flopped backward and landed flat on her back in the snowy mud. She kicked her arms and legs out in a swift jumping-jack motion and began making a snow angel. “Thanks a bunch, Zacky!”

“Oh, man, she’s literally losing her mind!” Rice said as he watched her body suddenly slacken and her head loll to one side.

“Well, she’s not going to be an angel for much longer,” Zack said, crouching beside her. “Zoe, help me flip her hoodie around before she reanimates!”

“Yeah,” Rice agreed. “Like a straightjacket.”

As Zoe leaned in, Madison’s eyes shot open and she gnawed furiously at the air, snapping her teeth viciously together. Zack held zombie Madison’s shoulders against the ground, trying to avoid getting bit by the undead mean girl.

Zoe pulled Madison’s arms out from the sleeves while Rice flipped the one-hundred-percent-vegan sweatshirt on her backward. Zack cinched the drawstrings around the hood now covering her face, and Rice crisscrossed the sleeves behind her and tied them in a knot.

“There,” Zack said, brushing off his hands. Zombie Madison was zombie-proofed and ready to go.

“Nice job, guys, but now we gotta move out,” said Ozzie, strapping on his backpack.

“Wait,” Zack said, and lifted Ozzie’s binoculars to his eyes, peering out across the Niagara River one final time. “I want to make sure Twinkles isn’t still out there.”

They all paused for a moment, except for zombie Madison, who wriggled back and forth in her sweatshirt straightjacket, steamrolling her own snow angel.

“I still don’t see him,” Zack said, gazing through the binocular lenses.

“Poor Twinkles,” Rice said. “What a way to go.”

“Yeah,” said Zoe. “If Rice didn’t throw like a girl, none of this ever would have happened.”

“Shut up, Zoe,” said Rice. “I don’t throw like a girl.”

“Tell that to Twinkles,” she said. “And Ozzie’s nunchucks.”

“Nunchaku,” Ozzie corrected her with a deep hollow sadness in his voice.

Zack wanted to tell his sister to be quiet, too. He needed to think. Things were starting to feel a bit out of control. At least there weren’t a zillion zombies everywhere now that they were in Canada. “Come on, Twinkles,” Zack whispered under his breath. “No Zombie Chaser left behind.” He took one last glimpse out at the river still teeming with zombies but saw no sign of their beloved pet. “I don’t know what else to do.” He turned and shrugged to the rest of them.

“There’s nothing else we can do, buddy,” said Rice. “Except go and find Olivia.”

“I guess you’re right,” said Zack, a single tear streaming down his cheek. “I’m really going to miss that little guy.”

As they hung their heads in a moment of silence for Twinkles, a strong gust of wind squealed with a high-pitched yowl.

“You hear that?” Zack asked, his ears perking up a bit.

“I didn’t hear anything,” Zoe whined. “It’s probably just the zombies.”

“There it is again!” Zack said, listening intently.

The noise now sounded more clearly out of sync with the wind’s powerful howl. “Arf-arf-arf!”

“That’s no zombie.” Zack moved toward the bushes along the riverbank in the direction of the yips. He pushed a few branches aside and peered over the underbrush.

“Ruff!” Twinkles came trotting out of the brambles and leaped off the ground into Zack’s arms.

“Twinkles!” Zack shouted, clutching the little pup to his chest. He spun around to his friends.

“Twinkles?” Ozzie, Rice, and Zoe all gasped, triple-jinxing one another.

“Blarghles!” Madison echoed.

“Arf!” Twinkles barked at his zombified owner. The little pup was shivering nonstop and whimpering a bit, but other than that he seemed perfectly all right.

“I think he’s okay,” said Zack, drying him off with a spare T-shirt from Rice’s backpack. “We just have to get you warm and dry before you catch a chill, don’t we?” he asked Twinkles, and ruffled the frost out of his fur.

Now reunited with their canine pal, they climbed up a small slope to get back to the roadway along the riverside then strolled down the Canadian street. Madison followed them like a demonically possessed mummy, lumbering slowly and growling behind the hood covering her zombified face. The sweatshirt fabric was now soaked with excess drool, and bubbles of slobber bulged and popped off the hoodie when she grunted.

A ways up the road, the five of them took shelter at a metro bus stop, piling into the enclosed glass waiting area and huddling together on the cold metal bench. “Hopefully a bus will come soon and pick us up,” Zack said, trying to stay positive.

“Here’s hoping!” Zoe said as she tied up zombie Madison to a signpost.

“Well,” said Rice, peering at the posted schedule, “it says there should have been a bus here like five minutes ago.”

“Aw, man,” Zack said. “We just missed it!”

“No, wait,” Ozzie said, pointing down the silent, empty road. “Check it out.”

The kids squinted their eyes to the end of the street as a city bus rounded the corner. The bus rolled to a stop at the curb, and the kids hopped off the bench ready to board.

The passenger door opened and the bus driver looked down at them from behind the steering wheel. “What stop?” he asked.

“We don’t know, really,” said Zoe, and took out Madison’s phone to show the bus driver the address. “We’re just trying to get here.”

“You’re going to want the Maple Ridge stop. Then it’s just a couple blocks away,” he said. “You going to hop on or what?”

Ozzie climbed up the staircase first, then Rice boarded the bus holding Twinkles. Behind them, Zack and Zoe struggled to push Madison up the staircase next.

“What’s the matter with your friend?” the driver asked as he raised his eyebrow at the snarling weirdo concealed by her backward-sweatshirt straightjacket.

“She’s an escaped mental patient,” Zoe said about her undead BFF. “She goes a little crazy sometimes.”

“Well, is there any way to make her stop? I can’t be having her making a ruckus on my bus.”

Zack winked at his sister as he pulled out a small bottle of ginkgo biloba from his pocket. “She just needs to take her medicine,” he said, shaking the bottle.

The driver rolled his eyes and waved them aboard as the mechanical door closed behind them. “Next stop: Niagara Falls!”

A little while later, the bus jostled over a set of railroad tracks as they drove up Clifton Hill. Both sides of the street were lined with restaurants and nightclubs, arcades and mini-golf courses, and haunted houses and wax museums.

“Ooh!” said Rice. “There’s a haunted house called Nightmares? Can we stop?”

“Sorry,” the bus driver called back. “This isn’t a tour bus, and these places don’t open until the nighttime.”

“What a bummer.” Rice pouted in his seat.

Zoe elbowed Rice in the shoulder. “Dude . . .”

“What?”

“We have more important things to do than go to a haunted house,” Zoe said. “Get your head in the game.”

As they drove onward, Zack felt a surge of urgency rushing through him. They had to find Olivia and soon.