The Aldens walked all around the downstairs. There were no stools or stepladders in sight. The chairs they found were either too large to move or too delicate to stand on.

  The children returned to the library and looked at the stacks of books they still had to shelve. “We can’t just leave them like this,” said Jessie.

  “Maybe we should find Mrs. Blackwell,” said Benny.

  “No, she said it was important not to bother her,” Henry said firmly.

  “What can we do?” asked Violet. “She also said she’s counting on us to finish this today.”

  The Aldens stood silently for a moment, thinking. Then Jessie spoke. “I’ll go upstairs and take a quick peek around. Maybe there’s a stool up there. I won’t bother Mrs. Blackwell.”

  Jessie went quickly up the stairs while the others waited in the library. “Hello?” she called softly. She didn’t want to bother Mrs. Blackwell, but she also didn’t want to intrude on her without warning. It was eerily silent upstairs. “That’s strange,” Jessie muttered to herself. “It feels so empty up here.” She quickened her pace.

  Jessie peeked cautiously into the study. There was no sign of Mrs. Blackwell. As she turned to leave the room, Jessie spotted a small stepstool in the corner. “That’s what we need,” she said to herself. She picked up the stool and was about to go back downstairs when she noticed a strange light coming from the sitting room. It looked as if something inside the room was giving off a red glow. Jessie walked slowly into the room.

  Off the sitting room was a tightly closed door. Above the door was a single bare lightbulb. The light was glowing red.

  Was that there before? Jessie wondered. No, she told herself. Or if it was, it wasn’t turned on. I would have remembered that strange glow. Jessie did remember the door the light was over. She had asked about the door when Mrs. Blackwell gave them the tour of the house that morning. Mrs. Blackwell hadn’t answered the question about what was behind it.

  Jessie picked up the stool and hurried out of the room. She was suddenly anxious to be back downstairs with her sister and brothers.

  “You found one!” Violet said when Jessie returned with the stepstool.

  “Yes,” said Jessie, putting it down. She felt calmer now that she was back in the library.

  “Did you see Mrs. Blackwell?” Henry asked.

  “No, I didn’t see or hear her anywhere,” said Jessie. “But I did see something else.”

  “What?” Benny asked, instantly curious.

  “Remember that door off the sitting room?” Jessie asked.

  “You mean the one that Mrs. Blackwell didn’t show us because she’d already put the boxes away?” Henry said.

  “Exactly. That door was still closed and there was a weird red light over it,” Jessie told them.

  “Huh,” said Henry, shrugging. “I guess they like colored lights.” He picked up the stool, placed it close to the bookshelves, and climbed the two steps. Violet carried over some books and began handing them up to him.

  “I don’t think that’s it,” said Jessie. “There aren’t colored lights anywhere else in the house. That light was weird. It seemed almost like a warning light.”

  “A warning about what?” asked Benny.

  “I don’t know,” Jessie answered. “A warning not to enter that room, I guess.”

  “Maybe that’s her office,” Violet suggested. “She did say she had work to do and didn’t want to be bothered.”

  “But have you ever seen an office with a warning light outside?” Jessie asked.

  “It is a little unusual,” Henry agreed. “But it wouldn’t be the first unusual thing we’ve found here.”

  The others went back to shelving books, but Jessie just stood there, lost in thought.

  It was close to dinnertime when the Aldens finished with the library. They stood back to admire the shelves and shelves of neatly arranged books.

  “Looks great,” said Henry, “if I do say so myself.”

  The children left the stepstool in the library and let themselves out, as Mrs. Blackwell had instructed. The house was dark and silent. Henry pulled the front door shut behind them.

  As they walked down the driveway, the Aldens noticed a man standing near the street. He had brown hair and was wearing a brown leather jacket. He was staring at the Blackwells’ house as if deep in thought.

  “Hello,” called Henry. “May we help you?”

  The man seemed startled to see the Aldens. He looked at them without saying a word, then began walking quickly down the street toward a car parked at the curb.

  The Aldens reached the end of the driveway. “Is there anything —” Henry called out, but the man was already in his car, closing the door. A moment later, he had driven away.

  “That was strange,” said Henry, looking up the street in the direction the car had gone. “He hurried away the minute he saw us.”

  “Without even saying hello,” Violet added.

  “He seemed very interested in the Blackwells’ house,” Jessie said.

  “And you know what’s even stranger?” Benny said. “That was the same man we saw at lunchtime, the one who was watching us from his car.”

  “Are you sure?” Violet asked.

  “Yes,” said Benny. “SPIDER2.”

  CHAPTER 4

  Lights at Night

  Over dinner that night, the children told Grandfather all about the mysterious Blackwells and the mystery man. When they reached the end of their story, Benny started to giggle.

  “What’s so funny?” Jessie wanted to know.

  “The Blackwells are spies,” said Benny. “And now someone’s spying on them!”

  “I can’t help wondering if that man has anything to do with what Mrs. Blackwell said on the phone,” said Jessie. “Could he be the one Mrs. Blackwell is tracking?”

  “We don’t know for sure that Mrs. Blackwell is tracking someone,” Violet pointed out.

  “Violet is right,” Grandfather agreed. “Mrs. Blackwell’s phone call does sound surprising, but I’m sure there’s a simple explanation.”

  “Really?” Benny asked. “Like what?”

  Grandfather thought for a moment. “I’m not sure,” he admitted. “But I wouldn’t worry about it. Hearing one side of a telephone conversation always sounds odd.”

  The Aldens finished their dinner, then Henry and Violet cleared the table and Jessie and Benny washed the dishes. When the kitchen was clean, the children joined Grandfather in the living room. They played checkers and read books until it was time for bed. Saying good night, they each headed into their own rooms.

  Henry walked over to the windows in his room to pull down his shades when something outside caught his eye. From the window next to his bed, Henry could see the side of the Blackwells’ house. Because Henry’s bedroom was on the second floor, he could see over the tall stone wall that surrounded the Blackwells’ property.

  Henry studied the side of the house. On the first floor was a long row of windows. “That must be the room down the hallway where Mr. Blackwell works,” he said to himself. The shades on the windows were drawn, but the lights inside were on. Henry could see the shadow of someone moving around inside.

  Henry looked at his clock. It was nine o’clock and Mr. Blackwell was still at work. That seemed unusual. Grandfather sometimes worked late, but he was usually finished before nine. “I wonder what kind of work Mr. Blackwell does,” Henry wondered aloud. He pulled the shade down firmly.

  Henry put on his pajamas and brushed his teeth. Checking the window again, he saw that Mr. Blackwell’s light was still on. He slid into bed and picked up his book. After reading a chapter, Henry sat up and peeked out the window. The light was still shining. Henry closed his book and turned off his lamp. “Tomorrow we’ll go back to the Blackwells’,” he murmured sleepily. “Tomorrow we’ll find some answers.”

  Several hours later, Henry woke up with a jolt. A noise outside had awakened him. It came again — a long, mournful howl.

/>   Henry gasped as his bedroom door suddenly swung open. Then he relaxed. It was Violet.

  “Did you hear that noise outside?” Violet asked softly.

  Henry nodded. The howl came again. “I think it’s a cat,” he said.

  “Do you think it’s hurt?” Violet asked, sounding worried. She walked over to the window next to Henry’s bed and lifted the shade. The two children peered out into the dark yard, trying to see the cat. “I don’t see anything,” said Violet.

  “I do,” Henry replied. “Look.” He pointed to the Blackwells’ house. The house was dark except for the light coming through one window on the first floor. Behind the drawn window shade was the shadow of a person.

  “I think that’s Mr. Blackwell’s study,” Henry told Violet. “He’s been up working all night.”

  Violet’s eyes popped open in surprise. She glanced at Henry’s alarm clock. “But it’s three o’clock in the morning!” she said. “What could he be working on at this hour?”

  Henry shook his head and settled back into bed. “I don’t know, Violet,” he said. “But we’re good detectives. Maybe we can find out tomorrow.”

  The next day, as the Aldens walked to the Blackwells’ house, Henry and Violet told the others about seeing Mr. Blackwell working all night.

  “Wow, they keep some late hours,” said Jessie.

  “Whatever their secret mission is, it must be super urgent,” Benny said, sounding excited.

  They were approaching the Blackwells’ fence when a white car pulled up to the curb ahead of them. A man got out of the car and stepped out onto the sidewalk. He had dark, wavy hair and a small, well-trimmed beard. The man was holding a large piece of paper and looking up and down the street.

  “I wonder if that man’s lost,” said Violet. “It looks as if he’s checking a map.”

  When the Aldens reached the man, Henry said, “Excuse me, do you need help?”

  The man looked startled. He quickly rolled up the paper and tucked it under his arm. Turning to face the children, he smiled broadly. “Hello!”

  “We saw you were looking at a map,” Jessie said. “Perhaps we can help you. We live around here.”

  “A map?” The man looked confused. Then he seemed to understand. He waved the rolled-up paper under his arm. “Oh, yes, this.” He shook his head. “No, I’m not lost, but thanks for offering.” He put out his hand to shake Henry’s. “I’m Joe Toll.”

  “Hello,” said Henry. “I’m Henry Alden. These are my sisters and brother.”

  “You said you live around here?” Joe Toll asked.

  “Yes, right up the street, Mr. Toll,” said Henry.

  “Call me Joe,” the man said with a smile. “Seems like a nice neighborhood.”

  “Yes, it is,” said Henry.

  “How about your neighbors? Nice people?” Joe wanted to know.

  “Yes,” said Jessie, raising one eyebrow. “Our neighbors are very nice. Why?”

  “How about the people in this house here?” Joe motioned to the Blackwells’. “You seem to be headed in that direction. Do you know them well?”

  “Not really,” Henry replied. “They just moved in.”

  “Oh, they did?” asked Joe. “Did they just build the house?”

  Benny spoke up. “You sure have a lot of questions! How come you want to know so much?”

  For a moment Joe looked uncomfortable. “Me? Oh, I just …” His voice trailed off. Then he smiled. He gestured toward the Blackwells’ front gate. “I was just admiring this nice spider gate,” he said. “I’m interested in spiders and I, uh, I wondered what kind of people would have a gate like that.”

  Henry nodded slowly. For some reason he didn’t quite believe Joe.

  “We’re about to go see them,” said Benny.

  “You could go with us and we’ll introduce you,” Jessie offered.

  “Oh, I uh … um … since they just moved in, they must be very busy,” Joe said quickly. All of a sudden he seemed nervous. “Gotta run!” He quickly got back in his car and drove off.

  “How odd,” said Henry.

  “You said it,” said Jessie. “I don’t think he was telling us the truth.”

  “If he just wants to know about the gate, then why was he asking all those questions about our neighbors?” asked Benny.

  “I have no idea,” said Violet.

  “He seemed especially interested in the Blackwells,” Henry pointed out. “Just like that man yesterday.”

  Benny’s eyes opened wide. “Maybe Joe Toll is a spy, too.”

  Henry ruffled Benny’s hair. “Now you’re starting to think everyone’s a spy!”

  “Not everyone,” said Benny. “Grandfather’s not a spy. And Mrs. MacGregor’s not a spy!”

  “It’s weird he was looking at a map, since he says he wasn’t lost,” Violet pointed out.

  “That is kind of odd,” Jessie agreed.

  “I wonder if it really was a map,” Henry said. “I mean, most maps fold up, and he rolled that one.”

  “Maybe spy maps roll instead of fold,” said Benny.

  “And it looked like that paper was mostly white with only a bit of writing on it,” Henry continued. “Maps usually have lots of colors and writing on them.”

  “Hey, look!” cried Benny, pointing to the sidewalk. He bent down and picked up a small piece of paper. “Joe must have dropped this.”

  “What does it say?” Henry asked.

  Benny was just learning to read. He sounded out the letters, “Bl … bl … black …” He took a breath. “Blackwell. Hey! I think it says Blackwell!”

  Henry looked over Benny’s shoulder. “You’re right. It does say Blackwell. And that’s their address. I wonder why he’d have that, especially since it sounded as if he didn’t know them.”

  The children were silent for a moment, wondering.

  “I don’t know,” Violet said at last. “But maybe we’ll find some answers inside.”

  “Come on, you guys,” Jessie said. “Let’s see if Mrs. Blackwell was pleased with the way we set up the books.” She led the way to the door.

  Mrs. Blackwell was very pleased with the books. As soon as the children came inside, she told them what a great job they’d done. “You organized the library really nicely.”

  Jessie beamed.

  “It was a huge help to me last night when I had some research to do,” Mrs. Blackwell went on.

  “What kind of research?” asked Jessie. Mrs. Blackwell seemed a little friendlier than she had been before. Jessie hoped that meant she would answer the Aldens’ questions.

  “Oh, just something for my work,” Mrs. Blackwell responded.

  “Were you working late last night?” Henry asked, remembering the light he’d seen.

  “No, I go to bed early,” she answered. “I’m a morning person.”

  Violet and Henry exchanged glances. Now we know that was Mr. Blackwell at three in the morning, Henry thought. He didn’t mention the light, however, because he didn’t want Mrs. Blackwell to feel he was spying on her.

  “Today it would be great if you could unpack the pots and the dishes,” Mrs. Blackwell said, leading the way to the kitchen. “My husband and I are getting tired of eating take-out food.”

  In the kitchen, the boxes were stacked up against the cabinets and on the counters. There were large boxes filled with pots and pans and serving bowls, and smaller boxes of dishes, glasses, and silverware.

  “Where would you like us to put everything?” Violet asked.

  “You kids did such a good job in the library,” Mrs. Blackwell said. “Why don’t you arrange it the way you’d like.”

  “Okay!” said Jessie. She was pleased that Mrs. Blackwell trusted them with that responsibility.

  “We’ll get right to work,” said Violet.

  As she was walking out, Mrs. Blackwell noticed a box with a red marking on the top. “This one doesn’t belong in here,” she said to herself.

  Jessie jumped at the opportunity to ask, “Wha
t does that marking mean anyway?”

  “I told you, those boxes are my husband’s,” Mrs. Blackwell said.

  “I was just wondering if that shape meant something,” Jessie said.

  “That shape?” Mrs. Blackwell seemed to be considering something. After a few seconds she said, “No. Nothing.” As she turned to walk away, the phone rang. Mrs. Blackwell hesitated, then handed the box to Benny. “Could you take this to my husband, please? I’m going to answer that in the other room.” She turned quickly and walked out.

  Benny looked down at the box.

  “I’ll take that,” Jessie said. “Mrs. Blackwell said to be very careful with those.”

  “I can be careful,” Benny told her. “She asked me to take it.”

  Before Jessie could stop him, Benny walked out with the box. Although the box was small, it was a heavy one. He groaned softly so the others wouldn’t hear and carried it to the back hall.

  When Benny reached the hallway, he stopped and put the box down. He shook out his arms, which were tired from carrying the heavy box. “Now where do these marked boxes go?” he said to himself.

  He looked down the hall. It was long, dark, and narrow. At the end was a closed door with a light glowing underneath. “That must be the place,” Benny said to himself. It didn’t look very welcoming.

  Benny took a deep breath and began to walk slowly down the hallway toward the door, wondering what he would find behind it. When he got to the end of the hallway, Benny set the box down again. He looked at the closed door in front of him. Then he knocked softly on the door. There was no response, so he knocked a little bit louder. Still no response.

  Benny cautiously tried the doorknob.

  The door creaked open, revealing a brightly lit room.

  A male voice called out angrily from within, “Please don’t come in!”

  “I’m sorry!” Benny said. He quickly shut the door. He hadn’t seen who the voice belonged to. Mr. Blackwell must have been on the other side of the room, behind the door.

  Benny had seen only one thing clearly before shutting the door. Next to the door was a large glass case.