“Good morning, everyone!” Sylvia called out. She was standing behind the food table, holding a glass of orange juice.

Dink opened his eyes and blinked. The lights were bright, and he smelled something that made his stomach rumble. He sat up and stretched. The anagram book slid off his sleeping bag to the carpet.

Dink reached over and poked Josh’s sleeping bag. “Josh, wake up! Someone stole all the food!” he whispered.

Josh’s head popped out of the bag. “You’d better be teasing,” he growled.

“Would I tease you?” Dink asked. He grabbed his backpack and headed for the bathroom. Mr. Davis and Alex were just coming out. Alex had toothpaste on his lips.

“Quite a night, wasn’t it?” Mr. Davis said to Dink. Alex walked over to the River Diamond, which was back inside the dome on top of the pedestal. The fence was in place, and someone had swept the floor.

“I’m glad no one was standing near Spino when that board fell,” Dink said.

“Righto,” Mr. Davis said.

In the bathroom, Dink was surprised to see a man combing his hair at one of the sinks.

The guy noticed Dink and smiled. “Hi!” he said. “You must be with the sleepover. Enjoying it?”

“It’s been great,” Dink said. “Until the alarm went off last night.”

“Yeah, bummer,” the man said. “Oh, I’m Trevor. I’m the museum paleontologist, which means I study fossils. I started out as a police detective, then decided I’d rather look for dinosaur clues than crooks.”

“I’m Dink Duncan,” Dink said. “I’m here with my dad and two of my friends.” He unzipped his backpack and took out his toothbrush and toothpaste.

Trevor waved good-bye and left.

Dink stood in front of the mirror and began brushing his teeth. Rinsing his mouth, he noticed a dark hair on the sink where Trevor had been standing. He took a closer look. The hair looked the same as the straight black hairs Josh had pulled off his shirt last night.

Dink gently wrapped the new hair in a paper towel and stuck it in a pocket. Then he pulled a clean T-shirt from his backpack. As he tugged the one he’d been wearing over his head, he felt something stick his ear. He ran his fingers over the cloth and found a wood splinter.

Dink plucked out the sliver. It was pointy as a needle. When did I rub against something made of wood? he asked himself. Then he remembered shoving the plank off the River Diamond last night. He figured that the sliver must have stuck in his shirt while they were moving the plank.

Then he realized that the sliver was in the exact same place where the hairs had been on his shirt. Which meant that the hairs probably came from the plank, too. But how did the hairs get onto the plank?

Dink tugged on the clean T-shirt and combed his hair with his fingers. He decided that maybe one of the museum workers had rubbed his head against the plank, leaving behind the three hairs.

But the workers all wore hard hats, didn’t they?

Josh rushed into the bathroom. “Dude, they’ve got pancakes!” he said.

“Awesome. I’m starving,” Dink said.

“And scrambled eggs and sausage!”

Dink left the bathroom while Josh was brushing his teeth. The ladder that had fallen was now leaning against a wall. The plank was once again high up, making a bridge between two sturdy ladders.

“Morning, Spino,” Dink said as he walked past the skeleton. In the sleeping room, he dropped his backpack and hurried over to the breakfast table. Sylvia and the other chaperones were helping people fill up their plates. Ms. Walker was in line ahead of Dink. Dink noticed that her hair was light brown. Her two little kids were still in jammies. Their hair was blond.

Dink took a plate from the stack. “Eggs, Dink?” Sylvia asked. She was wearing the bracelet that Ruth Rose liked. The chunks of stone and metal clinked when she moved her arm.

“Yes, please, and a couple of pancakes, too,” Dink said. Sylvia spooned some eggs onto his plate, then added two pancakes.

He felt something poke his back. “This is a stickup!” a hoarse voice whispered. “Gimme your pancakes!”

Dink turned around and saw Josh’s grinning face. “I’m so hungry I could eat a dinosaur,” he said.

“Better than the other way around,” Ruth Rose said.

She liked to wear all one color. Yesterday, she’d worn all blue. Today, she had on orange pants and an orange sweatshirt and headband. Even her socks and sneakers were orange.

Dink laughed. He poured syrup over everything, grabbed an apple juice, and headed toward his sleeping bag. His father was sitting with Mr. Davis, so Dink joined them. A few minutes later, Josh and Ruth Rose carried their plates over.

“Where’s Alex?” Dink’s father asked Mr. Davis.

“Over there, behind an open book,” Mr. Davis said. He grinned. “The kid is always reading and making plans. He can’t decide if he wants to become a writer or a gemologist. Last week he wanted to be a detective.”

“What’s a gemologist?” Josh asked.

“Someone who studies gems,” Mr. Davis said. “Alex is nuts about rubies, diamonds, and emeralds. He made me bring him here to see the River Diamond.”

Just then Dr. Wurst and the museum workers came into the room. They all loaded up plates and sat in a group, eating.

After breakfast, everyone rolled up their sleeping bags and got their stuff together. Mr. Davis and Alex walked over to say good-bye.

“Let’s keep in touch,” Dink’s father said. He and Mr. Davis exchanged email addresses and phone numbers.

Mr. Davis handed Dink’s father his book of crossword puzzles. “I didn’t get to do any puzzles,” he said.

“Oh, I need to return your anagram book,” Dink’s father said. “Do you have it, Dink?”

“Yup,” Dink said. “In my backpack.”

“Keep it,” Mr. Davis said. “I have plenty more at home.”

Dink felt someone tug his shirt. It was Alex, holding one of his books. He pulled Dink a few yards away from the others.

Alex had on a baggy sweatshirt and jeans. His sneaker laces were untied, and his glasses were so smudged Dink didn’t know how the kid could read anything through them.

“What’s going on, Alex?” Dink asked.

“It’s fake!” Alex whispered.