Mercy's Chase Read online

  Twelve inches of snow had fallen, but public transportation was still running, and Vida insisted on maintaining her office hours even though the college had cancelled classes. Daniel had no such work ethic, or at least not one that trumped what he called “Salem Time.” He’d asked her about the Affine Cipher on their way back from the sledding hill. Salem’s legs had felt like they’d been filled with cement, she’d walked back up that sledding hill so many times, but when Daniel had offered to pull her home on the sled, she’d chosen instead to walk alongside him.

  “A fine cipher?”

  He’d laughed and stopped to spell it in the snow, his mittened finger gliding through the powder like a skier, leaving behind his looping cursive. “Close. It’s spelled like this—a-f-f-i-n-e. You remember what a Caesar Cipher is?”

  Her dad had been doing some form of puzzle with her since before she could walk, starting with a wooden alphabet puzzle with dowels sticking out of each letter. Salem could put the correct letter in the correct spot before age one, graduated to jigsaw puzzles, and moved on to Japanese puzzle boxes and Rubik’s cubes before hitting mathematical ciphers. The Caesar shift was one of the most basic. Julius Caesar used it in his correspondence, settling on a single number and then substituting every letter in the alphabet for the letter that number of shifts from the original. So, if he selected the number three, A would become D, B would become E, and so on down the line.

  “Sure,” Salem had said holding out a tongue to catch a snowflake. Her dad had promised hot chocolate when they returned to the house.

  “The Affine is a substitution cipher, just like the Caesar, but more complex. Here’s the formula it uses.” He scooted to a clean patch of snow and carved these letters in:

  E(x) = (ax + b) mod m

  Salem’s eighth grade class had not yet covered algebra, but her private tutor had. “What does ‘mod m’ stand for?”

  Daniel had grinned. Salem loved that smile, the one that said he was proud of her. “The number of letters in the alphabet. So, if we are using the English alphabet, the m is…”

  “26!”

  “You betcha. The x represents the normal position of the letter in the alphabet. If we’re still using English, that means a is a 1, b is a 2, c is a 3, and so on. Make sense?”

  Salem had nodded. The math formula glistening in the pristine snow, her dad at her side, was everything right in the world. “Can I crack one?”

  Her dad had laughed out loud. He erased the formula—he knew she’d already stored it in her head—and replaced it with

  dbinl arhfd

  It took Salem three minutes to realize she’d need a slightly different formula to decrypt, another minute to create it, and two more to crack the code. “It says Salem rocks!”

  Daniel had whooped, drawing the stares of families still on the sledding hill. “She sure does. And I think she’s earned a helping of whipped cream on her hot chocolate. What do you think?”

  “A double helping,” Salem had said, a smile on her face.

  Daniel beamed at her, then glanced back at the snow writing. A worried expression flashed across his face. He glanced up, and then to each side, as if someone would care that a father and daughter were writing in the snow.

  “What’s wrong, Daddy?” Salem asked as he erased his writing.

  “Nothing.” His smile was planted back on his face when he stood up, but Salem wasn’t buying it.

  “You look scared,” she said.

  He tapped his chin, his smile becoming more natural, almost mischievous. “I see you’re not only good at math. You’re also a wizard at reading people.” He crouched so they were eye to eye. His cheeks and nose were rosy from the cold. “You know how sometimes girls don’t get as much talking time as boys?”

  Salem puffed up her cheeks. She sure did. The conversation had started last year when only boys were elected to the second-grade student council despite Salem and another girl running. Then Salem had noticed there were not very many pictures of girls in any of her schoolbooks, particularly her history textbook. It came to a head when they reached the civics unit in their workbook and Salem and her classmates discovered there were only 67 women between both houses of congress, while there were 468 men. And only a handful of those women with brown skin, like Salem’s own mother. Salem had never been a fighter, not like Bel, but fair was fair.

  “Yeah?” she said.

  “Well, it’s not right, but it does have benefits.” He leaned over to whisper. “If you spend your whole life living on the outside, you learn to study those inside the circle, the powerful, the men who make the decisions. Learn to read them, Salem, and to trust your own instincts. If the world isn’t smart enough to see you, use that to your advantage.”

  His words had tickled. She’d nodded, not because she understood but because she wanted hot chocolate. She’d grabbed his hand and they’d walked home together, silent.

  He’d taught her to read much more complex ciphers after that, but none of what she’d learned seemed to apply to the code carved into the back of the St. Brigid’s cross.

  “It could be an address,” Charlie offered.

  Salem was committing the code to memory, her brain working angles and algorithms. “Possibly. Or a date. I need to get at the B&C.”

  Charlie held out his good hand, pulled it back, and then offered it again. “May I?”

  Salem nodded, and he took the box from her. He squinted as he studied it. “We’ve traveled forward a bit in time, eh? Cut jewels inlaid in silver is a far cry from two-ton rocks transported and scratched on.”

  “Yeah,” Salem agreed. “We’re no longer dealing with Neolithic cryptographers, for sure.” She stood, favoring her injured leg. “Whoever originally built Stonehenge meant it as a clue directing the seeker to the Standing Stones of Stenness. The flowers around the Standing Stones would have then sent a person in the know to the Flower Rock. Bode had said the Flower Rock was originally a slab covering some sort of container. My guess is that whatever was originally at the end of the Stonehenge train was hidden inside.”

  “A bit farfetched.”

  “Not back then,” Salem said. “There were few monuments at the time. Stones and flowers would have been excellent markers—permanent ones—to a people who had not yet learned to write. A treasure buried three clues deep, whispered only among a select group, would be safe through the ages.”

  “Until the Order, or the Underground, began sniffing around.”

  Salem squared her shoulders. “I think the Underground originally built Stonehenge.”

  Charlie scowled, or at least appeared to. When he began laughing, she realized his wounds had disguised his laughter as the opposite. “Now you’re cooking with gas!”

  “You agree?”

  “Of course I do. I told you that my mother was a spy for the Underground. I guess I’ve always been an honorary member, and now I’m actively serving. On accident.”

  The sun ducked behind a gray cumulus cloud, dousing them in shadow.

  Charlie continued. “And so, the Underground, five thousand years ago, hid a treasure three clues deep, with Stonehenge being the first. Then what?”

  Salem had been wondering the same thing. “Something spooked them. Maybe the Order found out, or some random archeologist was close to stumbling across whatever is at the end of the train. The Underground sent a member to move the treasure further out, creating more clues between the beginning and the end of the train. The same thing happened with the Beale train. The Underground thought someone was getting close and had Emily Dickinson move it deeper. If that’s what happened here, we can expect the clues to get much more complex moving forward, more modern. The Order must not have been able to crack them. That’s why they brought me in.”

  A thought struck Salem that punctured her hypothesis. “But then why would they have attacked us here? Cut the rope with
me at the end?”

  “The Grimalkin.”

  Salem shook her head. She wasn’t familiar with the term.

  Charlie winced. Salem couldn’t tell if it was the words or the pain of speaking. “He’s an assassin with the Order. Nobody knew what he looked like, before today. He’s famous for three things: his anonymity, his cleverness, and his penchant for toying with those he eventually kills.”

  “The Grimalkin plays with his victims?”

  “Yeah. Gets his rocks off on it. Based on what I’ve heard—and mind you it’s third-hand rumors—he’d get a real giggle at making this endeavor more difficult for you. He still wants you to reach the end, but it’s entertaining to him if you know he holds the strings.”

  Charlie closed his eyes and flexed his hand, his voice growing distant. “The car pulled up a half an hour after you dropped into the cave. Bode said he’d check it out. Figured it was tourists, and he could send them on their way by flashing his geological access pass, tell ’em something about the area being closed due to unstable conditions. Only the driver got out. He looked like a regular Scot. I half watched them, half kept an eye on the hole, ready to call you back up.

  “I heard you yell something, so I tried to get closer to the edge. When I looked over my shoulder, Bode was on the ground. I stood at the same time the bloke from the inn exited the passenger side of the car. He was smiling. He hit me with something.” Charlie lifted his chin, revealing a bullseye pattern, the center of it a black hole the size of a pen tip. “I dropped like a deer. Feels like they smashed my face pretty well, and I’m missing a finger.”

  Charlie tried a laugh, but the sound grew dark at the end. “Hopefully that’s all they did to me, eh? I grabbed a moment of consciousness, just enough to kick the backup rope to you, and then I went back to la-la land.”

  “I saw him, the man you were talking about, at the inn. He was watching us leave. He reminded me of a … cat.” Salem’s throat grew dry. “You think he was the Grimalkin, and that he put the drawing down there?”

  Charlie nodded somberly. “Which means he’s solved the train, at least this far.”

  Salem swallowed. “Jesus. He’s insane.” A salt-laced wind blew across the prairie, trembling the yellow flowers clustered near the sea cave’s entrance. “Why’d they kill Bode?”

  Charlie glanced over at the body. “Because they could. My guess is I’m only alive because you need me, and you’re only alive because they need you. Once we arrive at the end of the Stonehenge train, the Grimalkin will kill us both. He obviously knows about the cross that was in the box. He’ll be waiting at St. Brigid’s Cathedral, sure as the sun rises.”

  Salem had already reached that conclusion. “We have to figure out a way to get ahead of him. If not in location, at least in logic. It would be helpful if we knew which member of the Underground was tasked with adding on to the Stonehenge train, like Emily Dickinson did for the Beale train.”

  “Have you dug around in the box?”

  Salem had not. The inside contained fragments of red silk at the edges where someone had removed the lining. She ran her fingers along the smooth silver interior. When that produced nothing, she pulled a pen knife from her bandolier to feel along the cracks.

  “Just smooth silver.”

  Charlie was watching her with total concentration verging on desperation. “What if there were two clues, and without the second, we go to the wrong spot? I don’t want to have lost my finger for nothing.”

  Salem’s brow furrowed. “I can’t find anything more.”

  “Can I see it again?”

  She handed the box back to him. He examined every jewel, crack, and corner. He smelled it. He looked ready to lick it. “I agree. The cross must be all there is.”

  Salem nodded and reached for the open box as the sun escaped the clouds.

  A flash of light dotted the bloody front of Charlie’s shirt.

  Salem’s heart squeezed.

  She moved the lid of the box. The flash of light appeared again.

  It was not a reflection off a jewel.

  “What do you see?” Charlie asked.

  Salem closed the lid and brought it to her face. She’d been rolled flat and pumped back up. She peered into an inset diamond, not wanting to utter her theory out loud until she was sure.

  “Holy. Shit.” Her hands were shaking.

  Charlie crawled closer. “You found something.”

  She pulled the box away from her eye, blinked to reset her focus, and peered in the diamond again, only it had turned out not to be a diamond after all. It was a lens. Her voice quavered. “Do you know what a Stanhope is?”

  “Never heard of it.”

  Salem wasn’t surprised. If she hadn’t been raised by Daniel Wiley, master of all things hidden, she likely never would have heard of them, either. He’d given her a Stanhope ring for her tenth birthday. It had a thick pewter band, a diamond-shaped head the size of a pencil eraser and also made of pewter, and a hole punched into the side of the head. He’d told her to peek into the hole. Salem had been delighted to see the image of her mother and father inside her Stanhope ring. She hadn’t thought of it in years. Last she’d checked, it was nestled in her childhood jewelry box back home.

  “The name comes from the third Earl of Stanhope, who invented a small, one-piece microscope in the 1800s. A different guy developed the microphotograph a little while after that. In 1857, a French inventor named Dagron combined the two, mounting a microscopic image on the end of a convex magnifying lens, the whole unit the size and shape of a Lite Brite peg. The result is basically a standalone peephole; you hold it up to the light, peek in, and can see a single photograph. It was the original viewfinder.”

  Charlie appeared hypnotized by her words.

  Salem’s voice was shaking as she finished her explanation. “Dagron was a spectacular salesman and designed hundreds of novelty items with nearly invisible Stanhopes built into them: rings with pictures of naked ladies, crosses with the Lord’s prayer, pens with a photo of the Eiffel Tower, all of it hidden unless you knew to look through the tiny hole.”

  She held the box out to him and pointed at what she had thought was a recessed diamond.

  He held it up to his face.

  When she blinked, she could still see the image on the inside of her eyelids. It was a negative of a muddy black X drawn in a staccato hand, a white circle marking where the two lines of the X crossed. The gray background broke in a diamond shape around the X, its blurriness suggesting movement, a gyroscope forever spinning as the world stood still.

  When Charlie lowered the box, it was clear he’d also recognized the image inside the Stanhope. It was a copy of Rosalind Franklin’s famous Photo 51, the X-ray that proved DNA’s double helix structure.

  42

  Orkney Islands, Scotland

  They huddled in the car outside the apothecary. Charlie had volunteered to go in. If his parka was zipped to his throat, most of the blood soaking his shirt was hidden. There was no way to hide the damage to his face, which was taking the color and shape of overcooked pot roast, but at least he could walk without dragging a limb.

  Salem stuffed money into his unmangled hand. The other would remain in his pocket. He would buy clean shirts, pants if they carried them, antiseptic, bandages, and painkillers. Wounds licked and clothes swapped out, they’d do their best to get on the next plane to Dublin.

  Bode’s body was back at the Gloup, a blanket tossed over him.

  It broke Salem’s heart to leave him there, but she’d agreed it was the only option. They could not involve local police. She’d wanted to contact Agent Bench, or have Charlie pull strings at MI5, so at least Bode could get a proper burial.

  “There’s good points to that,” Charlie had said, driving one-handed. “And it’s possible that the only reason the Grimalkin has been so effective at following us is
he knew all along where we’d be going, at least up until the next step, St. Brigid’s Cathedral. But what if there’s more to it? What if my boss, or yours, is filling the Order in on our activities? Wouldn’t be the first time.”

  No, Salem thought, it certainly wouldn’t. Still, when Charlie walked into the apothecary, she’d held her phone. It itched in her palm. She wanted to tell Lucan Stone what they had learned and where they were going next. But what if he was the one who’d been feeding the Grimalkin the information she’d sent to him?

  She tucked her phone back into her pocket, watching locals walk down the street. Kirkwall appeared to be a lovely town. She imagined it was full of salt-of-the-earth people. They deserved better than conspiracy and murder. She and Charlie needed to get out of here before they brought more bad. He was right that it would be best to call in an anonymous tip on Bode once they were safely in Dublin. It didn’t feel good, but she couldn’t risk being detained here.

  The driver’s door opened. Charlie slid in. “The pharmacist asked if I’d been in a good fight. Told him he had no idea.” He held a large bag toward Salem. “Got everything we need, though. You take care of yourself while I drive, and I’ll wash up at the airport parking lot, yeah?”

  Salem nodded. She dug around in the bag and pulled out a pair of gray sweatpants. They were so clean, so normal, that they made her want to weep. Underneath them was a roomy navy-blue t-shirt with Orkney Islands written across the front in plaid.

  “Limited selection,” Charlie said apologetically.

  Salem returned to the bag, searching until she hit on the bottle of antiseptic, a roll of gauze, butterfly closures, and a scissors. She set the rest of the bag in the back seat and took the scissors to her jeans. Her leg was too swollen to take them off naturally, so she’d need to slice them, all her modesty gone out of necessity. The waistband was difficult to cut through. Once she’d breached that, she could rip the rest of the way down, working toward her ankles.