“Yeah, fine,” I said.

  “Then let’s keep moving,” he said, “while we think.”

  The sky was clear, and stars were visible above the trees in the park, like pinpricks of light against the black. Dad didn’t know the city too well, so we wandered a bit before we came to the streets running along San Francisco Bay.

  There were large warehouses every few blocks jutting out into the water. You could see (and smell) that most of them were still working warehouses and part of the fishing industry.

  “This is a main avenue called the Embarcadero,” he said. “Let’s follow it north for a bit. Wade, if you can’t read the poem . . .”

  “I can do it.” I took out the notebook and flipped through the pages until I found it.

  Scorpio

  The deadly claws of scorpion

  Lie quiet in jade’s green tomb.

  Its guardian stands masked of face

  And sinister of hand.

  Seek him no more, no more

  Upon this moving earth.

  No one said anything while a crowd of tourists walked past us, chatting loudly; then Darrell cleared his throat. “Well. We get the first two lines, right? The Scorpio relic was in the box. But the rest of it is about who the Guardian is. And I have to say, the last two lines seem like he’s dead, which is not good news.”

  “Maybe.” Lily lifted her phone as if she was going to check it, but she didn’t. “Let’s forget the last two lines for a second. ‘Masked of face’ sounds like the Guardian has a mask. But you’d notice some guy going around with a mask, and he’d probably be locked up, so maybe it’s not a real mask but more like a disguise. And he’s sinister and dangerous. Who do we know like that?”

  “Who don’t we know like that?” I said.

  “Right, everyone has been sinister so far, including Feng Yi,” said Becca.

  Darrell stopped suddenly on the sidewalk, and stayed there until we turned back to him. He was grinning. “Uh, no. The poem doesn’t say ‘sinister’; it says ‘sinister of hand.’”

  “So he’s holding a gun,” I said. “Or maybe . . . a throwing star?”

  “So maybe the Guardian is Mr. Feng,” said Lily.

  Still grinning, Darrell shook his head. “Not what I meant.”

  “Good one, Darrell,” said Dad, sharing the smile now. “You figured out that part. The poem writer knows that sinister comes from Latin, and it means ‘left.’ The poem means that the Guardian is left-handed.”

  “Mr. Chen!” said Becca. “His left hand was the one that . . . the one . . . that . . . you know . . . is missing!”

  Looking at Becca made me think of the diary. “Wasn’t Andreas left-handed? The diary says so, right? Becca, it’s in your translation.”

  Lily reached into Becca’s bag and handed her the notebook. Becca opened it and skimmed a few pages. “Here it is. When Andreas is on the island, Hans says, ‘His left hand, with which he is most adept, is black.’” She looked at me, and her eyes shone like stars under the streetlight. She knew what I knew: the puzzle pieces—some of them—were starting to fit.

  “So,” Lily began, “we’re saying that there’s some kind of tradition, from Andreas on down, for the Guardians, the true Guardians of Scorpio, to be left-handed. That it’s all left hands from the very beginning of the relic.”

  “Mr. Feng isn’t left-handed,” I said. “The way he tossed throwing stars. The way he reached for me from the pagoda roof.”

  Darrell stopped again and stared at the ground. “Say that again.”

  “I said Mr. Feng isn’t—”

  “Not you,” he snapped. “Lily. Say what you just said.”

  She blinked. “I said there’s a tradition that the scorpion Guardian has to be left-handed.”

  “Whoa,” said Darrell, hopping in place on the sidewalk as if he couldn’t get it out fast enough. “This whole thing just got a little bit nuttier and a whole lot weirder, and you are going to love me even more, if that’s even possible, which it probably isn’t—”

  “Darrell, please,” said Dad, unable to keep from smiling.

  “Yeah, catch us up already,” Becca said impatiently.

  Darrell positioned himself under the nearest streetlight as if it were a spotlight. “Maybe it’s a slim lead, but there is totally one left-handed guy we’re all forgetting about, except that I just remembered him.”

  “Darrell,” Dad said. I could tell from his tone that even he was getting impatient. “Who are you talking about?”

  “The cabdriver!” he said. “The snobby driver with the all-wrong Stratocaster!”

  CHAPTER TWENTY

  Like everyone else’s, my mind zoomed back to this morning to the grumpy bearded cabdriver at the airport who’d told us to beat it.

  He drove a wrong-sided British car. His guitar was strung for a left-handed player. He was left-handed. He had even said so. But . . .

  “Isn’t that too much of a coincidence?” I said. “The first person we see in San Francisco happens to be the relic Guardian? And you’re saying this because he has a lefty guitar? I’m not sure that even counts as a slim lead.”

  Lily nodded. “More like nonexistent.”

  “Is it?” Dad stroked his chin slowly. He pulled us away from the spotlight and down by the side of one of the warehouses. It smelled like fish and salt water. “Darrell, say what you were going to.”

  “Well,” he said, “Wade, you keep saying that there are no coincidences, which I agree with. Besides that, it’s actually amazingly logical. Mr. Chen sat next to you because he knew you were . . . with me, a Guardian.”

  “Very funny,” I said.

  “Fine, but just listen. The Hong Kong Guardian flies to meet the San Fran Guardian, right? The Frombork Protocol means they need to move the relic. So they meet to figure out a plan.”

  “What about Mr. Feng?” asked Becca. “What’s his part in this?”

  “Just a minute.” Darrell’s brain was obviously popping, and he couldn’t be sidetracked. “So the Guardian for here is in disguise as he’s supposed to be. As a nasty cabbie. ‘Its guardian stands masked of face / And sinister of hand.’ He’s got a beard. And he’s nasty as a disguise, so he doesn’t have to pick up regular people. Except yesterday he was waiting for Mr. Chen, all disguised and left-handed because he and Mr. Chen have to do the Frombork Protocol. Ta-da!”

  Dad frowned as he always does when he’s thinking deeply, then he turned. “Let’s keep moving.” We made our way back to the street and continued north.

  I still wasn’t sure I bought it. “Darrell, are you saying the cab driver shows up at the airport every day to pick up a Guardian in case one comes? And he doesn’t pick up anyone else? How does he make any money?”

  Darrell shrugged, but Lily started nodding. “No, I get it. Maybe he’s superrich, so he doesn’t have to pick up just anybody. Or maybe he only comes on certain days of the week. There’s a certain day that Guardians come or something.”

  Then I remembered. “Mr. Chen told me that when we woke up it was going to be Sunday. Today. But I don’t know . . .”

  “Actually, Darrell could be right,” Becca said, getting into it now, while Dad just listened carefully. “Let’s say the driver is there every Sunday, like clockwork. Clockwork, right? It’s all about time. Anyway, the Guardian doesn’t show. So the driver takes off, leaving us to take a shuttle. So why doesn’t he do his job as a taxi driver? Because that’s not his job.”

  “But your own question,” I said to her. “How does Feng Yi fit into this? Why wouldn’t he get into the cab?”

  Darrell jerked his finger in the air. “Because the cabbie knew he wasn’t a Guardian, sort of proving that Feng Yi is a bad guy. What if we call the cab company or whatever, and find out who that driver is? His left hand is what Mr. Chen’s missing one was supposed to shake!”

  Becca smiled. “Very poetic, Darrell. But how can we find him? There must be hundreds of cabdrivers.”

  “Not with that kind of
cab,” Dad said. “I haven’t seen another—”

  “Got it.”

  Amazing Lily had already looked up a central number for city cabs on her phone, which she handed to my dad.

  I knew his brain was clicking fast when he stretched his shoulders, pressed the numbers on the phone, and stared away from us. He was pulling himself together, ready to be sneaky again.

  “Hello,” he said. “My name is Rrr . . . Ronald Korman. I’m a photographer for—”

  “Best American Cities!” Lily whispered.

  “Best American Cities, and I’m here in San Francisco on assignment to take photos for our next edition. I saw a vintage English hackney cab at the airport, and I’d like to track down the driver. . . .”

  Darrell nudged me. “Smooth operator.”

  A woman on the other end spoke.

  “Oh, is he?” Dad said. “I see. What else can you tell me?”

  After listening for a minute, he said, “I will, thank you.” He hung up and gave Lily her phone. “Our guy is definitely an oddball. Most of the drivers dislike him, you never see him except on Sundays—”

  “I knew it,” said Lily.

  “—and even then he won’t pick you up. About the only real thing she could tell me was that his writing name is Papa Dean.”

  “Writing name?” asked Becca.

  Dad chuckled. “He’s known as the cabdriver poet. No last name. No phone number. Then she said that he lives ‘off the grid’ somewhere in Sausalito.”

  “Which means what?” asked Darrell. “Little Sausage?”

  “No,” said Dad.

  “Where’s Sausalito?” asked Lily, raising her phone.

  “It’s across the bay, on the other side of the Golden Gate Bridge.” My dad pointed far up the street. “It’s famous for its . . . houseboats.”

  “Houseboats . . . ,” I said slowly. I locked eyes with Dad. “‘Seek him no more, no more / Upon this moving earth.’ Papa Dean doesn’t live on this moving earth. He lives on the water.”

  “In a houseboat in Sausalito,” my dad said.

  “Yes!” said Darrell. “I did it!”

  “You?” As usual, Lily had leaped upon the information and already had a satellite map of the houseboats on her phone. “There are hundreds, maybe thousands, of houseboats. And if he’s off the grid we have no way . . .”

  She stopped, studying her screen. “Bec . . . what do you see here?”

  “Where?” Becca asked.

  “Here!” said Lily, tracing her finger on the screen. “Look!”

  “What is it?” asked Darrell.

  Becca laughed. “I knew Tricia Powell was telling us the truth!”

  “All right, spill already,” I said. “What are we seeing here?”

  “The symbol we found in the spice box,” Lily said, bringing up the image we had shown Feng Yi.

  “It was never a Chinese character,” said Becca, “though someone wanted us to think it was. Instead, it’s a map.”

  “Of what?” asked Darrell.

  “Of this.” Lily wiped the screen away from the symbol to a very grainy satellite image of one section of the Sausalito houseboat docks.

  “Holy cow!” said Darrell.

  “I bet the dot in the symbol points to the houseboat,” Becca said. “That’s where we’ll find Papa Dean, the Guardian of the Scorpio relic!”

  Dad half smiled. “You guys, this is good. Very good. Sara would be proud of how we’re piecing all this together. But there’s a problem. Feng Yi saw the symbol, too. He may have realized that the symbol is a map, and if, somehow, he didn’t die in his fall, he may already be on his way to Papa Dean’s. If he lied to us about the map, he’s not a Guardian.” He adjusted Wolff’s black satchel on his shoulder and scanned the traffic. “I have the feeling we’re the last people to get this clue. Wade, draw the symbol in the notebook—”

  “Let me trace it!” said Darrell, which he did, after placing a page of the notebook over the phone’s screen.

  “Now Lily, erase the symbol and the satellite map,” Dad added.

  “Erase . . . ,” she said, puzzled at first; then she nodded. “You’re right. You’re right. We don’t need anyone else getting it.”

  “We need to find that houseboat as soon as possible,” said Becca, starting down the street. “And this time, let’s get a real cab!”

  CHAPTER TWENTY-ONE

  As we waved at oncoming cabs, I thought: We’re doing it again. We’re putting it together. Re-creating the past. Making connections, just like we did in Berlin and Rome and Guam. Everything we’d figured out since we got to San Francisco was because we’d unpuzzled the puzzles together.

  The murder of Uncle Henry might have forced us to start the journey, but we were moving on our own now, and it was an awesome thing.

  What was not awesome was the taxi situation on the Embarcadero at night. On our long trudge up the street, we hailed every cab we saw. None of them stopped, not even when Lily jumped up and down on the sidewalk.

  “Come on!” she groaned. “We’re more important!”

  “Can you find a cab service, Lily?” asked Dad. “We’ll just have one meet us up the street.”

  She found one and called. Even then, we had to wait almost a half hour. By the time we tumbled into the taxi, the stars sparkled, the moon was high in the sky, and it was nearly eleven p.m.

  “The bridge,” said Darrell, “to Little Saus . . . to Sausalito.”

  “You got it.” The driver, an older woman, chuckled in a voice like gravel rolling around a metal pie plate.

  When the cab started moving, I felt we were finally getting somewhere. Maybe it was that—or maybe it was when the investigator suddenly called Dad from Brazil, saying that Sara was “nearby, so keep the phone close”—but when we nearly cried with relief, our stomachs cried, too. After the good news, we realized we were starving.

  Dad asked the driver to pause for a few minutes so we could grab some takeout at a place called Fisherman’s Wharf—a famous area of restaurants and stores—before the drive across the bridge to Sausalito. No problem, she said, pulling over at the first opportunity. She even recommended a place.

  Lily, Becca, and Darrell stayed in the car, while my dad and I stocked up on—what else—Chinese food at a cool restaurant overlooking the water that was just closing up for the night.

  But when we got back outside, the cab was gone. Darrell stood alone a few feet from where it had been, his eyes wide, his body tense.

  I slowed. “What’s going on? Where are Becca and Lily?”

  Darrell nodded toward the overhang of a nearby warehouse that had been converted to a game arcade. Music jangled loudly from inside. There, in a rainbow of lights around the door, stood Markus Wolff, dwarfing both Becca and Lily, who stood in front of him.

  I plainly saw a gun pointed at Lily’s side, while Wolff held Becca firmly by her wounded arm. Her brown hair was soaked and clinging to her shoulders; her face was tight with fear.

  Dad thrust the food bags at me and took a step toward the overhang, but Markus Wolff gripped his pistol more tightly.

  “Do not move another inch,” he said.

  Dad stopped.

  “How did you find us?” I asked sharply, but my voice was hoarse and weak. I caught Becca’s glance. Her eyes were wet. She was shaking.

  “A surprising question after our discussion about computing power in Honolulu,” he said. “Dr. Kaplan, kindly give me the object belonging to Mr. Chen.”

  Darrell drew up next to us. “The tile? It’s at the museum—”

  “Not the tile. The tile was merely an entry object into the search for the scorpion. I want the final object. I want his hand.”

  “His . . . ,” I started.

  A breath of impatience from Wolff. “The hand Feng Yi stole from Mr. Chen after he murdered him on the plane.”

  “He murdered Mr. Chen?” I asked.

  “Please, the hand. It is, I imagine, in the black satchel you have hanging over your should
er. Mr. Feng’s bag.”

  My dad glanced at the strap, then slid the bag off his shoulder and held it out to the German. “This is Feng Yi’s bag? He said it was yours.”

  “He lies.”

  “So Mr. Feng is . . . alive?” I asked.

  “For the moment,” Wolff said. He pushed Lily toward us. “Take the bag,” he said. Her hands trembled as she took it from my dad. “Now,” he said, “open every compartment.”

  “I can’t. One has a computer lock,” she replied in barely a whisper. “Which I guess you don’t know, since it’s not your bag.”

  “Ah . . .” Wolff removed his hand from Becca. Dad went for her and Lily, and Wolff let him pull the girls back to us.

  “You will wait,” Wolff said. He snapped a picture of the lock with his phone. We heard the whoop that the phone made. Some two or three quiet minutes passed, the crazy arcade lights blinking on all of us but the music now off. None of us moved; none of us spoke a word; no one passed by. Then his phone lit up. He studied the image on its screen, closed it, then tapped several numbers into the combination lock. I heard a small click, and the bag opened.

  What had he called them? The Copernicus servers? The computing power that put NASA to shame.

  Wolff removed something from inside the bag, and my stomach twisted.

  Wrapped in heavy cloth was the prosthetic hand of Dominic Chen.

  Its thumb and fingers were nearly extended. Its slightly concave palm was open, as if waiting to hold something in it.

  It was obviously not real. It was mechanical, but with something nearly alive about it.

  His gun still out and trained on us, Markus Wolff examined the hand carefully as he turned it over and over. It seemed less like a hand than an intricate piece of machinery, made of aluminum and wires.

  “Well, then, we are done,” Wolff said finally, inserting the hand back into the satchel. “It is not essential that I remove you here and now, so I will not. But pray our paths do not cross again in San Francisco.”

  He bowed his head slightly as he slung the bag over his shoulder, his gun now deep in his coat pocket. “And thank you for your other information, too.” He turned his back on us, and, as he had done before on the street outside the hotel, he seemed to vanish into the crowd of tourists.