Mom took her hands off the steering wheel and looked over her shoulder at Dan. “Your sister’s almost at the slide. Don’t you want to go with her?”

Dan squirmed within his seat belt. “Not really.”

“Are you sure? Your dad and I used to love to play here when we were kids,” Mom said.

Dan slipped his hand into his pants pocket and squeezed the hard, gold medal.  “Fastest Boy in Mrs. Peabody’s Class,” it said. He’d won it last month before school ended.

“I’m sure,” he said.

Mom sighed, opened her car door, and stepped outside.

Dan watched her through the window. Any minute now, she would call Page back, and the three of them would return to the house where Grandpa lived before he disappeared. It was the same house he and his family now lived in.

Mom glanced down at Dan. “You’ll like it here,” she said.

“No I won’t,” Dan said.

Mom cocked her head to one side. She smiled the way she did when she hid a Christmas or birthday present behind her back. “Try the swings first, Page,” she called to Dan’s sister. “They’re amazing.”

Page turned and waved.

Dan undid his seatbelt. He opened his door. “What’s so amazing about the swings?”

Mom smiled her secret smile again. “You’ll have to find that out for yourself.”

“Oh, all right.” Dan climbed out of the car.

“Race ya, Dan!” Page called. She started running.

Dan ran too. Within seconds, he zipped past Page and jumped onto the first tree swing.

“Take care of your little sister,” Mom called.

Why? They weren’t going anywhere. “All right,” Dan called back. He then pushed his air-light sneakers into the sky.

Page jumped onto the tree swing next to his. She kicked off her sandals.

“Look! I’m higher than the other trees!” Dan said.

“So am I,” Page said.

“Now I’m higher than the Rocky Mountains.” Dan pumped his swing higher, but when it also went faster, he gritted his teeth. He clenched the swing chains.

“What’s happening?” Page yelled.

“We’ve got to jump off these swings!” Dan said. Then he jumped.

Clouds whisked past him. Wind whooshed like the inside of a hollow tunnel. The playground . . . then Mom . . .  disappeared.

THE HIDDEN KINGDOM

Dan landed on his stomach with his face pressed flat against the ground.

“Are you all right?” Page whispered.

Dan moaned. He wanted to say, “I don’t know. Are you?” But his mouth was full of dirt.

“I think so,” Page said. “Nothing hurts.”

That’s weird! Dan thought.

“What is?”

Dan spit out the dirt. “Page?” he thought again. “Are you moving your mouth when you talk?”

“No,” Page answered. “Are you?”

“No. All I do is think the words and you hear them.”

“Same with me. Cool, huh?”

“Cool. And strange. Have you opened your eyes yet?”

“Nope. I’m afraid to look. When we jumped, I couldn’t see the playground anymore.”

“Me neither,” Dan said. “Let’s both open our eyes at the same time. Okay?”

“Okay. On the count of three. One . . .”

“Two. . .”

“Three,” they said together. Both opened their eyes.

“Where are we?” Page said.

Right in front of them, Dan saw a tall, rocky mountain. It went straight toward the sky.

“I don’t know,” he answered. “Mom said we would be surprised. Do you think this is what she was talking about?”

“Maybe.” Page frowned.

“Your voice is wobbling,” Dan said. “Are you all right?”

“I feel like I did the first day I went to Kindergarten.”

That’s how Dan felt too—all scared inside—but he didn’t want his sister to know. He wanted her to think he was brave. So he looked over his shoulder away from her.

“AAAAAAAH!” Page screamed. “We’re on the edge of a mountain!”

“Don’t look down!” Dan grabbed her hand. “We’ll be all right. Let’s climb away from here.”

Inch after inch, Dan and Page climbed up the face of the rocky mountain until it flattened into a large, green field. The grass was sprinkled with tiny gold and purple flowers.

They crawled a few more feet into the field then stood. Safe again.

Page squeezed Dan’s hand tighter. “Are we still in the Rocky Mountains?”

Dan looked around him. He saw a circle of sharp, jagged mountains with a valley in the middle. The mountains were covered in thick, moss-like grass and lots of tall, bushy trees.

Some of the trees were dark green. Some were deep red. And some were bright gold. A shimmering castle stood on top of the tallest mountain on the other side of the valley.

“I don’t know where we are,” Dan said.

“You are in the Hidden Kingdom,” said a gravelly voice.