The police—including Officer Jones, Cody’s mother—arrived moments after the two security guards had cuffed Geoff. The maids were talking to an officer who knew Spanish, while a few hotel guests gathered behind a police line, hoping to see what all the commotion was about. Cody and the other kids stood by and watched as two officers took the handcuffed man away. As Geoff passed by Cody, he glared at her, sending a cold chill down her spine.

Cody’s mother approached the kids, who were huddled together, watching the scene.

“Ooookay,” she said, hands on her hips and standing at attention in her uniform. “You want to tell me what happened here?”

Cody looked at the others, hoping they’d step up and explain the situation, but they remained mute and stared at the floor. Cody took a deep breath. “We were …”

Cody’s dad suddenly appeared from down the hall. “Dakota! What happened? What are you doing here? I thought you were at the Berkeley campus working on a school project.”

“I was just asking her the same thing,” Cody’s mom said to him.

“Dad, what are you doing here?” Cody asked, repeating her dad’s question.

“Your mother called me. What’s going on?”

“I’m trying to tell you,” Cody said, feeling frustrated at the interrogation. “We were looking for … diamonds.”

“What?” her dad asked, his face a picture of disbelief.

“It’s a long story, Dad,” Cody began to explain. “It started the day before our trip to Alcatraz. I got this strange e-mail message. It was a poem that hinted about there being some kind of treasure on the island. So when we went on our field trip the next day, we looked for clues.”

Mr. Jones seemed to go pale. He slapped his hand on his forehead. “Oh, no … I didn’t mean …”

Cody squinted at him. “Dad? What’s wrong?”

He looked at Cody’s mom, then glanced at the four kids. “I’m the one who sent that e-mail message. Since you kids love secret codes and messages so much, I thought it would be fun to send you on a sort of treasure hunt around the prison island. But you were never meant to end up here.”

Officer Jones glared at her ex-husband. But before she could speak, Cody asked, “You wrote that poem? You sent us looking for those seats? And inside the lighthouse?”

Mr. Jones nodded until she asked the last question. “Inside?” he asked. “No. The clue was on the outside. It was supposed to lead you to another clue, and that clue was to lead you to the exercise yard, then the gardens, and then the gift shop. The last code said, ‘Surprise! Love, your dad.’ I hid it under a book about Alcatraz in the shop.”

Cody frowned, remembering the note about ringing a bell—and that she hadn’t had a chance to read the rest of the message before the guard snatched it out of her hands. She glanced at her friends.

“I didn’t see that note until we were leaving the lighthouse, and then I forgot about it because we assumed it had something to do with the Campanile bell tower. When we first came to the lighthouse, the door was open, so the note was hidden. The guard said we could go inside if we were quick—so we climbed up to the top. We found a message carved into the wall that gave us directions to the Campanile. He must have overheard us talking about finding the diamonds during the tour—and again in the lighthouse—and followed us to the campus, then here. I thought it might have been Matt the Brat or even Diamond Dave following us, but it was the guard. He thought we would lead him to Diamond Dave’s stash.”

“Cody, you told me you needed to go to the campus to work on a class project.”

Quinn spoke up. “It was a project, just not a class project. Then when we got another clue at the Campanile tower, we wanted to follow it.”

“Another clue?” Mr. Jones asked.

“Yeah, the one that sent us here, to the Claremont,” Luke said.

“But that guard followed us,” M.E. added, nervously twisting her long hair into a spiral.

“So who is Diamond Dave?” Cody’s mom asked.

Her dad spoke up. “The ranger told the kids a story about Diamond Dave on the tour. I’d read about him online—that’s where I got the idea for a treasure hunt. But I had no idea it would lead them here. With a maniac following them.” Her dad suddenly looked tired. Cody knew that look: extreme worry. No wonder. She’d given her dad—and her mom—quite a scare.

“I’m sorry, Mom, Dad,” Cody said. “We thought we were just following clues to an old mystery. We figured if the diamonds were still there, it would be cool to find them.”

“And maybe buy some new night-vision goggles or a high-tech GPS for our club,” Quinn added.

“All right,” Officer Jones said. “I’m sure I’m going to have more questions for you later, but for now, I want you to go down to the restaurant and wait for me there while we finish up here. I’ll give you guys some money. Buy yourselves something to eat. And stay there!”

“I’ll go with them,” Mr. Jones said.

Cody’s mom nodded her thanks.

The kids headed for the elevator in silence and rode the car down to the lobby level with Mr. Jones, who kept glancing from one Code Buster to another, saying nothing. When they reached the café, the kids returned to the table they’d occupied earlier, and Cody’s dad pulled up an extra seat. She glanced out at Alcatraz, where all of this mess had really started.

“Dad—”

“Mr. Jones—”

“Kids—”

Everyone spoke at once. The kids stopped talking; Cody’s dad continued. “Look, guys. This is partly my fault. I shouldn’t have made up that treasure hunt. I had no idea you’d miss my clue and find clues to a treasure hunt more than fifty years old! But next time, let us know where you’re going. You were lucky this time.”

The Code Busters nodded.

The same waiter who had waited on them earlier—Delmar Morris—appeared and stood at attention, once again holding his hands together in front of him. Cody noticed the ring again and wondered if it was a university class ring, like her dad’s.

“So, you’re back for more lemonade and french fries,” the waiter said, a small smile playing at his lips. “And you’ve brought a guest?”

“This is my dad,” Cody said glumly.

“A pleasure to meet you, sir. What can I get for you all this time? Another round?”

“How about lunch?” Mr. Jones asked the others.

They nodded vigorously; they were all very hungry after having only a few fries and a drink earlier.

“How about five cheeseburgers,” Mr. Jones suggested to the kids. They nodded.

The waiter bowed slightly, then asked, “Did you find the laundry chute?”

Cody shook her head. “You were right. They’re gone, except for an opening in the wall that’s been sealed up.”

“But we found a message there,” Quinn spoke up.

“Really?” the waiter asked. “A message?”

“Yeah,” Luke said. “There was a drawing and the number four twenty-two—the same number as the haunted hotel room. When we got to the room, we realized that the drawing was of the chandelier in that room. We thought maybe there were diamonds hidden in there …” Luke trailed off.

“Ah, the diamonds,” the waiter mused. “You’re referring to that story I heard as a kid. When my father was the maintenance man back then, there was a fellow who insisted on staying in the haunted room—Room Four twenty-two—and paid quite a lot extra for it, I understand. The next day, my father was sent to the room to replace the chandelier. When he arrived, he found the fixture had been completely removed from the ceiling and had vanished, along with the mysterious fellow. He had to install a new one—not half as nice as the original. And he didn’t like being in that room. The ghost rumors, you know.”

“Did he see the ghost of the little girl?” M.E. asked.

“No—at least, he never mentioned it.”

“What about the diamonds?” Luke asked.

“He didn’t see any diamonds, but he found a crystal from the old chandelier, buried in the carpet. He had it made into a ring as a memento of the biggest theft ever to occur at the Claremont.” The waiter held up his hand. “He gave it to me before he died. I plan to give it to my son someday.”

Cody blinked when she saw the ring. The crystal in the middle of the bronze setting sparkled in the light. Could it be …?

“Well, if you’ll excuse me, I’ll get those cheeseburgers going.” The waiter hurried off.

Cody looked at the others. “Guys!” she whispered. “Did you see that ring on his pinkie finger?”

“Yeah, what of it?” Quinn asked.

Luke turned to Cody. “You don’t think …”

M.E.’s eyes brightened. “Do you think it could be?”

Cody’s dad held his hands up. “Whoa. Wait a minute. What are you kids talking about?”

“His ring!” Cody said. “What if it’s not a crystal, but a real diamond that was hidden in the old chandelier?”

The waiter returned with their drinks. As he set them in front of each place, the kids couldn’t take their eyes off his ring. After he placed the last drink on the table, Mr. Jones leaned over to read the older man’s name tag, then said, “Excuse me, Mr. Morris, have you ever had that ring appraised?”

The waiter chuckled. “Oh, no. It just has sentimental value, from my dad. I’m sure it has no monetary value.”

Mr. Jones met the waiter’s eyes. “I highly recommend that you do.”

The waiter’s eyes fluttered as he looked down at his ring. He cocked his head, smiled, and left the table.

Cody grinned at her dad. Something good might come out of this after all.

A few days later, Mr. Jones arrived unexpectedly at Cody’s mother’s house. The Code Busters were studying in Cody’s room when he entered. Quinn was on the floor, working on a math paper. Luke sat in the beanbag chair, reading a skateboarding magazine. M.E. was at the computer, and Cody lay on her stomach on her bed, looking over her spelling words.

“Hi, Dad!” Cody said. “What are you doing here?”

“Hey, can’t a dad come see his daughter and her code-busting friends when he wants to?” he asked.

“Uh … sure, I guess. So what’s up?”

Mr. Jones sat on the edge of her bed.

“I got a call,” he said.

Uh-oh, Cody thought. More fallout from their misadventure over the weekend. She tensed up, waiting for the bad news, certain her mother would ground her until she turned eighteen. “Yeah? From who?” she asked. “The hotel said they weren’t going to press charges against us, and they were actually glad that their security guards and maids had helped to capture Geoff.”

“No, not from the hotel, exactly. From the waiter, Mr. Morris.”

Cody sat up. “What did he want?”

“He had the ring appraised yesterday.”

Cody shivered with excitement. “Really?”

“You were right. The crystal turned out to be a diamond. And it’s apparently worth quite a lot of money.”

“You’re kidding!” Cody squealed. The other Code Busters high-fived at the news.

“And he wants to do something for the Code Busters, to thank you all.”

“For real?” Quinn said.

“Yes. He’s invited you all to a day of swimming at the Claremont and lunch at the Bayview Café. All the burgers and fries you can eat. And this will make you smile—he’s throwing in some tech equipment for the club.”

“Awesome!” Luke said.

“Sweet!” M.E. nearly shouted.

“How did he know where to find us?” Cody asked. “He must be a pretty good detective.”

“He remembered my name from my credit card, called me, and told me the news.”

Cody felt extremely satisfied with the results of their treasure hunt. “See, Dad? Being a Code Buster pays off.”

Mr. Jones patted her leg and stood up.

“Yeah, well, remember: snooping around in other people’s business can also get you into trouble. So enjoy your code busting, but don’t get carried away, hear?”

“Sure, Dad,” Cody said.

“Oh, and this must’ve fallen out of your backpack for you.” He handed her a large manila envelope. “Your mom said to bring it up to you. See you guys later.” He left the kids to their studies, closing the door behind him.

Cody studied the envelope addressed to “The Code Busters.” There was no return address. She opened it and found a sheet of paper inside. There appeared to be nothing written on either side. At the bottom of the envelope, Cody spotted a pen.

She held it up.

“What is it?” M.E. asked.

“I’m not sure,” Cody answered. She uncapped the pen, then began swiping it across one side of the paper. Letters were revealed.

“It’s an invisible ink decoder!” Quinn said. “Cool! It looks like someone wrote a message on the paper in invisible ink, and included the decoder pen! What does it say?”

Cody continued to color the paper with the pen, until all the letters were revealed. She held it up for the others to see.

“It makes no sense,” Luke said, looking at the ten-by-ten-square grid filled with random letters.

He was right, Cody thought. It didn’t make sense—yet. But four of the words jumped out at her immediately—the ones along the edges of the puzzle. She recognized it as a hidden-word puzzle. Inside the grid were strings of letters—going vertically, horizontally, and diagonally—that formed familiar words. Together the kids went to work on the puzzle, circling the words as they found them.

Soon they had a list of random words.

CARMEL

PIRATES

MISSION

TREASURE

WHERE

WANTS

THE

TO

VISIT

SEARCHED

FOR

WHO

Cody noticed the leftover letters were in alphabetical order.

“This is like an anagram of words,” M.E. said.

Cody began rearranging the words on a sheet of paper. It didn’t take her long to put the words together so they made sense.

Code Buster’s Solution found on this page.

“It sounds like we’re going on another field trip soon,” she exclaimed! “I’ll bet it’s from Ms. Stad.”

“Cool!” Luke said. “I love pirates. This should be fun.”

Cody looked at Luke. “Do you really think there’s a hidden treasure?”

Luke shrugged. “I guess we’ll find out soon enough!”