“Oh, that’s much better,” said Jessie, putting on the sunglasses.

  “The salt is reflecting so much light!” Henry agreed. “That sunglasses seller has the right idea.”

  With the sunglasses on, they were finally able to look around. The salt flat was a huge stretch of land, entirely covered in pure-white salt. It stretched into the distance on all sides of the road. Some parts were smooth, and others were cracked and rippled from the sun. Under the clear blue sky, it was breathtaking.

  “It really does look like snow,” Violet said as they walked out onto the salt. Benny reached down to touch it. The raw salt felt hard and light, like table salt. But the crystals were much bigger.

  “Can we eat it?” Benny asked. “It’s just salt, right?”

  “You could, but someone might have walked on it already,” Grandfather said with a wink. That didn’t bother Benny. Who knew when he would have another chance to eat natural salt? He picked up a cluster and tasted it.

  “So? How is it?” Jessie asked.

  “Salty!” Benny said, and they all laughed.

  Henry checked his watch. “I’m surprised we haven’t heard from a Reddimus agent yet,” he said.

  Jessie frowned. “Do you think something’s wrong?”

  “I don’t know,” Henry said. “We already thought the last message delivery was strange. And there was the problem of meeting up with Grandpa at the airport. Then we spent all the time to come out here, but no one’s come to find us…”

  “Maybe we got tricked,” Benny suggested. He didn’t sound too disappointed. Even if they had been tricked, they still had gotten to visit Salinas Grandes and eat natural salt.

  Violet sighed. “Mr. Ganert must have realized that we know he’s the spy by now. He even tried to come out with us this morning. Do you think the messenger at the airport was a spy?”

  “But the envelope had the owl sticker!” Benny said.

  Jessie took the envelope out of her backpack and looked at it again.

  “Yes, but Mr. Ganert has seen other Reddimus envelopes,” she said. “It wouldn’t be difficult for him to find an owl sticker and put it on there, just to make us think it was real.”

  “Plus, now that I look at it closer, the sticker doesn’t look as neat as the ones we usually see on the envelopes,” Violet said.

  Henry looked down at his watch to check how long they had been waiting. When he did, he noticed the snap on his camera bag was dangling open. With his heart racing, Henry opened the case and looked inside.

  “Oh no!” he cried. “The Reddimus box is gone! When could this have happened?”

  “It must have been while we were waiting to buy sunglasses!” Jessie said. “It was so bright we could hardly see anything, and there were so many people.”

  “Is Anna here?” Benny asked, looking around. Since buying sunglasses, most of the visitors had scattered and were wandering around and exploring. The five Aldens scanned the area. It was Violet who caught sight of a woman with a blond ponytail walking swiftly up the road to where the cars were parked. She was carrying something in one hand.

  “There she is!” Violet said, pointing. “If she makes it to her car, she’ll get away!”

  The children broke into a sprint. It wasn’t easy to run on the hard salt. Benny had shorter legs than everyone, and Violet slowed down so she wouldn’t trip. Jessie and Henry kept running, but Jessie was carrying her laptop in her backpack.

  “Don’t worry, Jessie!” Henry said. “I’ll get to her before she gets to her car!”

  “Be careful!” Jessie called, slowing down and leaning on her knees.

  Henry was a strong runner. In fact, that was how he had first met Grandfather, before he had known who his grandfather was. Once a year, Grandfather put on a free-for-all race, and one day Henry had decided to enter and had won. Now, as he ran against the clock to beat Anna Argent to her car and save the last Reddimus artifact, he remembered that day. Behind him, he heard Grandfather and his siblings cheering him on.

  “Run, Henry!” they cried. “You can do it!”

  “That’s my boy!” Grandfather shouted.

  The salt crackled and flew up under Henry’s shoes as he dashed onward, racing to catch up with Anna Argent. When he got closer, she noticed him and started running. She looked between him and her red jeep and realized she wouldn’t reach it before he would.

  “Give back the Reddimus box!” Henry called to her.

  “No!” Anna yelled back. And with that, she spun on her heel and started running in the other direction, onto the salt flats.

  By now, everyone around had stopped to watch the chase take place. Henry had already run what he thought was about a quarter-mile. He could easily run another three-quarters. But he wasn’t sure whether he would catch up to Anna. She was a powerful runner. Early in the Aldens’ journey, she had caught up with a moving train. In fact, Henry had never seen her without her sneakers on.

  Henry and Anna raced across the flats while all the visitors watched. The sun glared off the salt, and Henry’s legs began to ache. Anna was running right toward the edge of the flat. It seemed she hoped Henry would grow tired and give up so she could escape, but Henry was determined to catch up. He watched her silhouette against the bright salt, hoping that any moment she would start to slow down so he could gain on her.

  Suddenly, Anna’s form disappeared. Henry frowned and ran onward. Then he tried to skid to a halt—but it was too late. He tripped on a mound of salt, almost invisible in the white daylight, and went tumbling over the other side.

  Henry groaned. His elbow was bruised, and he was all wet. He had landed in a shallow pool of water. The fall had left scrapes on Henry’s knees and elbows, and the saltwater in the pool made the scrapes sting. Anna had also tripped and fallen in. She sat in the water next to Henry and hissed in pain, holding her ankle. It already looked swollen and bruised. The Reddimus box was still clutched in her free hand.

  Henry sat up and pushed his wet bangs from his eyes.

  “What is this?” he exclaimed.

  “A salt pool. What’s it look like?” Anna snapped. “I thought you would have figured that out by now.”

  “Please, I want to help you,” Henry insisted. “It’s a long walk to the road, and it’ll be difficult with your ankle like that.”

  Anna looked at Henry’s hand when he offered it, but instead she held the Reddimus box closer to her. “I’m not going to fall for your trick. You just want the box!” she said.

  “Henry, are you okay?” called a voice. It was Jessie. She, Grandfather, Violet, and Benny had come to see if everything was all right. Because they hadn’t been sprinting at top speed, they didn’t have any problems seeing the salt pool. Jessie and Benny waded into the pool and helped Henry up. They walked away from the pool a little so Henry could shake out the soreness from tripping. He even had grains of salt in his hair.

  “We were worried!” said Benny.

  “Thanks. I’m fine, but Anna’s ankle is twisted,” Henry said.

  Henry heard footsteps. Other visitors were coming to see what was going on. He brushed himself off. Already, the saltwater was evaporating off him, and the little scratches on his knees and elbows didn’t sting as much. It felt like they were evaporating too. Grandfather and Violet helped Henry sort out his clothes, which were disheveled from his fall.

  “¿Qué pasó?” asked one of the shopkeepers as he arrived on the scene. “Is everyone all right?”

  Another merchant said, “That was some race! Most excitement I’ve seen in years!”

  “I’m fine,” Henry said. “But there’s someone who’s been injured…”

  The Aldens looked back to where Anna had been sitting in the salt pool. She wasn’t there anymore. When they looked up, they saw her limping away across the salt flat on her hurt ankle.

  “Anna!” Jessie called. “You don’t have to go out there by yourself!”

  Anna didn’t respond or turn around.

  “Look,” V
iolet said. She walked out into the salt pool. The water came up to just below her knee. She picked up the little box that was floating in the water. “The Reddimus box!”

  “Do you think she forgot it, after all that?” Jessie asked.

  Henry looked out across the salt flat, watching Anna walk glumly away. She looked to be taking the long way back to the road where all the cars were parked. But if she kept going at her current pace, they wouldn’t have to confront her again. It seemed for the time being she had accepted defeat. That meant giving up the Reddimus box when she knew she couldn’t get away with it.

  “I don’t know,” Henry said. “I tried to help her, but she wouldn’t let me…I just hope there’s someone who she trusts.”

  A Clue and a Coordinate

  They went back to the car. Benny looked out the rear window as they left Salinas Grandes behind. Henry opened his camera case. The last Reddimus box was nestled safely inside.

  “Mr. Ganert can try to trick us all he wants, but the Argents aren’t getting this box!” he said.

  “I just hope we get another clue soon—a real one this time,” said Violet as they drove down the mountain path back to Salta. She looked through the back window with Benny, but no red jeep came down after them. They had gotten the best of Anna this time, but the fact was she was in Argentina and working with Mr. Ganert. The Aldens would have to be clever and careful to outsmart the two Argent agents.

  Grandfather returned the car to the rental agency when they got to Salta. Then he asked the rental manager for directions to a nice hotel. By the time they got checked into their room, the sun had set behind the mountains. They had something to eat, and just as they were brushing their teeth and getting ready for bed, Henry got a text message. It was from Trudy!

  Meet the contact tomorrow at noon, at the Casa Rosada next to the Plaza de Mayo, said the message. Henry read it out loud to his brother and sisters.

  “What’s the Casa Rosada?” Violet asked Jessie. “And Plaza de Mayo?”

  Benny tilted his head. “Like…mayonnaise?”

  Jessie laughed. “No, I don’t think so. Casa Rosada means ‘pink house’ in Spanish, but it is also a famous building in Buenos Aires.”

  “Like the White House!” Benny said. “Does the president of Argentina live there?”

  “Actually, yes, he does!” Jessie replied. “I remember from Spanish class when we watched a movie that took place in Buenos Aires. But I’m not sure what the Plaza de Mayo is.”

  “Hmm…the White House is near parks and plazas in Washington, DC,” Violet thought out loud. “Maybe the Plaza de Mayo is a plaza near the Casa Rosada.”

  “I think you are right!” said Grandfather. “On my way to Buenos Aires to meet you, the person next to me was telling me about the fantastic historical sites near the Plaza de Mayo and the Casa Rosada. I’ll book us an early flight back to Buenos Aires for the morning.”

  * * *

  The next morning, once the Aldens’ plane had lifted off, it was only two hours before it landed again in Buenos Aires. Although they had gotten up early to catch a flight, being in a new city was so exciting the children didn’t feel sleepy at all. Grandfather waved down a taxi, and they were off toward the Casa Rosada.

  Buenos Aires was a busy city humming with life. The roads were crowded with cars, buses, and pedestrians. Everywhere there were brightly painted buildings and street cafes with colorful patio umbrellas. Some of the cobbled roads were for foot traffic only.

  “Look there! Tango dancers!” said Jessie, pointing. Two dancers performed in the street. The man wore a sharp black suit, and the woman was dressed in a flowing purple dress. Tourists watched as they danced to music played by a musician nearby. Grandfather asked the taxi driver to pull over so the children could watch for a minute.

  “What kind of instrument is that?” asked Benny. “It’s like a baby accordion!”

  “It is called a bandonion,” explained their taxi driver. “An essential tango instrument.”

  The two dancers moved gracefully to the music. The woman was wearing high heels, but she didn’t trip once, even on the uneven cobbled road. When the song ended, the tourists applauded and whistled. Some threw coins in the hat near the bandonion player’s feet. The taxi driver shouted “¡Bravo, bravo!” before driving onward toward the Plaza de Mayo.

  “I want to learn to tango!” said Violet.

  The taxi dropped them off at the Plaza de Mayo, a square-shaped walking area the size of several city blocks. Many groups of tourists wandered the area, throwing coins into the fountains and taking pictures of the tall stone monument nearby. At the far end of the plaza was a huge mansion with many columns decorating the front. The mansion was colored salmon pink.

  “The Casa Rosada!” said Benny.

  “Wow, it really is pink, isn’t it?” asked Henry.

  The Aldens took their time exploring the plaza. There were gardens and palm trees and lots of pigeons. As the children and Grandfather neared the Casa Rosada, they saw a statue of a man holding a flag and riding a horse.

  “That’s Manuel Belgrano,” Grandfather said. “He created the flag of Argentina.”

  “That must be why he’s holding one!” Violet guessed.

  “Is it just me, or does that man near the statue look like someone who might be waiting for us?” asked Jessie. Standing under the statue of Manuel Belgrano was a thin man in a purple suit. Even his felt hat was purple. When he saw four children with their grandfather, he stood up straight and waved them over.

  “You must be the Aldens,” he said when they walked up.

  “Yes…and you must be a friend of owls,” Jessie said, looking at the man carefully. The owl was the symbol for the Reddimus Society. Asking someone if they were “a friend of owls” was the way Reddimus Society agents made sure they were talking to the right person.

  The man smiled. “My name is Nicolás, and I am indeed a friend of the owls. But I fear you may have met someone who was not.”

  “I’m afraid so,” Jessie said with a sigh. “A man gave us a fake clue at the airport. It sent us to Anna Argent, who tried to steal our artifact.”

  “Were you at the airport?” asked Henry.

  “I was there,” Nicolás said. “But I was at the wrong gate. It wasn’t until I heard your grandfather’s announcement over the loudspeaker that I figured out where you were. By the time I got there, you were all gone.”

  “Mr. Ganert must have gotten the gate changed and sent that man with the clue!” Benny said.

  “He probably planned on bringing us to Salta himself,” said Henry. “But then Emilio distracted him.”

  Jessie nodded. “We should have been more careful, but we were in a hurry. The final artifact needs to be delivered as soon as possible.”

  “Well, I’m very glad you’re all okay,” said Nicolás. “I’m going to tell you the next clue. I heard that our operation might have been compromised by the Argents, so I haven’t written it down. You’d do best to memorize it as well. If we don’t have a written copy, it will be impossible for the Argents to steal the clue and use it for their own good.”

  The Aldens nodded. It made sense. If they received a clue on a piece of paper, Mr. Ganert or Anna might be able to steal it.

  “Got it,” Henry said. “We’re ready.”

  The man cleared his throat and recited the clue:

  You’ve been to one of me already,

  The biggest ever built.

  But I am much smaller,

  So thin some call me an obelisk.

  I am important for this place—

  Look around and you will see.

  When was I built?

  After he finished, the man cleared his throat again.

  “That is the clue. Do you have it memorized?”

  “Can you repeat it one more time? I want to make sure we have it.” Jessie looked at her siblings. “Let’s each take a sentence. I will take the first one. Henry, you memorize the second sentence. Violet can take th
e third, and Benny can take the last one.”

  After the man repeated the clue, he asked them again if they had it memorized. They all nodded.

  “Then I will say farewell. Best of luck in your mission!” Without another word, the man in the purple suit walked swiftly away. Grandfather chuckled after he had gone.

  “The Reddimus Society sure knows how to dress snappy,” he said. “I am going to get myself a nice purple suit when we get back to Connecticut…ahem. So you kids got all that? I’m afraid I can remember only the first part.”

  “‘You’ve been to one of me already,’” repeated Jessie. “‘The biggest ever built.’ We must be looking for an object like something we’ve already seen.”

  “Something that’s the biggest of its kind,” agreed Violet.

  “‘But I am much smaller, so thin some call me an obelisk,’” said Henry, repeating his sentence. “What’s an obelisk?”

  “I think it’s a kind of monument,” Jessie said. “The Washington Monument in Washington, DC, is an obelisk. It’s very tall and has four sides, and it gets narrower as it goes up. On top it has a little pyramid.”

  “A pyramid!” said Benny. “We saw huge pyramids in Egypt. Aren’t those the biggest pyramids ever built?”

  Henry nodded. “That’s right, they are! So we must be looking for a smaller pyramid…one so small it is more like an obelisk!”

  “‘I am important for this place,’” Violet recited. “That must mean Buenos Aires. ‘Look around and you will see…’”

  Henry, Jessie, Violet, Benny, and Grandfather looked around. They were glad for their sunglasses in the sunny afternoon plaza. Violet was the first to notice the statue at the other end of the plaza. They had already seen it when they’d arrived, but it wasn’t until now that they thought anything of it.

  “There, by where we came in!” Violet said. “The monument with the statue at the top!”

  They hurried back down the plaza to take a closer look. The monument was solid and white, and Henry guessed it was more than fifty feet tall. It was the shape of a pyramid but much narrower than the pyramids in Egypt. It stood on a tall rectangular base. At the top was a statue of a woman holding a staff and a shield. She reminded Henry of the Statue of Liberty in New York.