Chapter 16

The work disassembling the mosaic was intense. Annja had to get up a few times and stretch her cramped shoulder muscles. Since the living room area was large enough, she brought out her sword for a while and went through some of the kata she'd been taught.

She was sore from the battles she'd fought. As always, focusing and becoming one with the sword left her more energized than exhausted. She returned to work with renewed focus.

Gradually, the tessera were all removed and placed on the table. When she was finished, she was ultimately disappointed.

There was nothing on the glazed marble behind them.

She stared at the picture of the dog she'd assembled on the table next to the glazed-tile background. She'd put each piece next to its mate, re-creating the picture because that was how she'd been trained to handle artifacts. Everything that was found together stayed together, in the same juxtaposition it had been found.

All that work, and she still didn't have anything to show for it.

Okay, you're frustrated, she told herself. Take the relaxing bath you've been missing the past few days and let the thoughts percolate for a while. Maybe a nap.

Retreating to the bathroom, she got a clothing bag out, stripped down, then dumped her clothing into the bag. She added the old clothes she still had. She enjoyed having new jeans, but until she'd had them for a while they didn't feel like her old jeans. She loved the comfort of familiarity, and the new jeans didn't feel lived in.

While the water ran to fill the tub, Annja went through the selection of bath fragrances and found some bayberry that smelled pretty good. She wanted a long soak, so she emptied the bottle in the water.

Her cell phone rang. When she got to it, Caller ID showed the number started with an international code. It was 06 and she knew that one belonged to Italy.

Dreading the call, knowing it was going to be from Mario's family because she'd told Bart to let them know they could call her, Annja answered the call. "Hello."

"Annja."

The man's voice surprised her. She didn't recognize it. "Yes. Who is this?"

"Pietro Silvestri. I'm – " He stopped himself. "I was Mario's brother-in-law."

"I remember you," Annja said, switching to Italian because she could tell English was difficult for him. "The soccer player."

"Yes."

Annja remembered Pietro Silvestri as quiet and shy among the burgeoning and boisterous family. She'd bonded with him because of that. He'd been early in his marriage to Francesca and not used to the family, either.

"I'm surprised that you remember me," Pietro said.

"I've got a good memory," Annja said. "Plus, as I recall, you and I were both uncomfortable in the madhouse."

Pietro chuckled. "Yes. The inmates haven't gotten appreciably better. Only now some of the loudness is caused by the three children Francesca and I have been blessed with."

Annja retreated to the bathroom and turned off the water. She sat on the edge of the tub, feeling the heat soak into her and enjoying the fragrance. It seemed to lift some of the heaviness.

"Are you guys doing all right?" Annja asked.

"Things are crazy around here. I think Dante and I are going to come for Mario's body. It would be too hard for anyone else."

"If there's anything I can do, please don't hesitate."

"I appreciate it, but there's not much to do at this point. This is just a very sad thing."

Annja silently agreed. She'd put off her own sadness by working, but that wouldn't last forever. Even though she and Mario hadn't seen each other in years, knowing he was gone forever hurt.

"How are you doing?" Pietro asked.

"I'm okay. Sad. But it had been a long time since I'd seen Mario."

"That's what he'd said. His sister always teased him about you. They told him he shouldn't have let you get away."

Annja chuckled. "I think we got away from each other. On purpose. Mario and I weren't exactly looking for anything permanent. We had a good time. It was nice to be friends. Simple."

A child screamed in the background.

Pietro sighed. "I think that was one of mine. You don't get simple after you have kids. I think kids were what made Mario finally want to settle down. He'd been around so many nieces and nephews that he started wanting to have kids of his own."

Annja hesitated just a moment, feeling bad about what she was doing, then forgave herself and said, "I'd heard Mario had someone in his life. Erene?"

"That's right. Erene Skujans. It's a strange last name."

"Not in Latvia. I'm assuming that's where Mario met her."

"Yes. He was over there researching something he was very excited about."

"Do you know what it was?"

"No. Mario liked being mysterious. He was always doing those puzzles – showing the kids how to make cipher keys so they could write messages to each other that their parents couldn't read."

"Playfair ciphers," Annja said, remembering Mario's instruction to "play fairly" with her authentication. She and Mario had whiled away some of the boring hours out at the dig site playing with the idea of codes. Mario had been fascinated by them, and his favorite had been the Playfair ciphers.

"I think that's what they were called," Pietro agreed. "Whatever he was doing, it consumed him."

"What do you mean?" Annja got up and went back to the living room, back to the mosaic and the pieces she'd pried from the background.

"He worked on this project for two or three years off and on. It was hard watching him sitting thinking about it, then not telling you about it."

Annja began turning the tessera over one by one, working through the rows.

"Whatever it was," Pietro went on, "Mario found out about it while working in Vatican City. That was one of the reasons he quit there."

"He left me a message and told me he was bored." Annja started on the second row.

"That was part of it. I know he said they were too restrictive there. Too many secrets, I suppose."

"Every culture has them." Coming up empty again, Annja started on the third row.

"After leaving Vatican City, Mario worked in Venice for a while."

"Doing what?" Annja started on the fourth row.

"He was a gondolier, if you can believe it."

"I can't."

"He was. Francesca and I went down there to see it for ourselves."

"Why would he take a job like that?" Annja moved on to the fifth row.

"He couldn't find anything else and he wanted to stay there. Whatever he was working on, it had him by the throat." Pietro was quiet for a moment. "He always wanted to be famous."

"I remember. So how did he get to Riga?" Annja asked.

"A few months ago, he told everyone he was moving there for a while. To sort some things out, he said. But you could tell he thought he was on to something."

"But no one knew what."

"No. Then he started seeing Erene."

"She lived there?"

"I believe she still does. One of the things that seemed to captivate Mario most about her was that she was a witch."

"A witch?"

"Yes. Mario seemed quite enamored of her because of that. She was supposed to be something like a hedge witch or a midwife. He said Erene knew a lot of things about plants and herbal remedies." Pietro paused. "Now we don't think we'll ever get to meet her."

"No one has a way of getting in touch with her?"

"No. We contacted Mario through his cell phone. If we don't find a way soon, she may miss the funeral. The most upsetting aspect about this is that Mario's killers are still on the loose."

Nearly halfway into the eight row of tessera, Annja turned over a cube and found a letter. Excitement surged within her.

"You never know," she told Pietro. "That could change at any time."

****

Annja sat looking at the back of the mosaic, at the secret that had been hidden beneath the surface. There was a message on the back of the tessera. The letters were painted on backs of the tiles. If she hadn't taken the tiles off one by one and placed them in the same order, she'd have lost the message.

If anyone else had taken the tiles off, they would have destroyed what Mario had left behind for her to find. There was no doubt that the message had been intended for her.

The message said, "Hi, Annja. I have no secrets from you. Remember, no Selgovae!"

"All right," Annja said quietly. "That's a no-brainer, Mario. What do you want me to see?"

The Selgovae were a Brythonic tribe from Scotland, and one of the main reasons the Romans had built Hadrian's Wall. It made sense that Mario would use that as a linchpin to get a message across.

But what was the message?

The first part consisted of six letters: "ESIREF."

The second part, on a line four rows down from the first, had twelve letters: "JVLPHNJEMXJW."

Annja took her digital camera from her backpack, then stood on a chair over the table to focus on the tiles. After adjusting the flash and the lens, she took three close-up shots. Then she put the camera away and tried to wrap her mind around what the letters meant.

At first glance the coded message didn't tell her much. Then she remembered what Pietro had said about the ciphers Mario had taught his nieces and nephews.

The Fairplay cipher had been Mario's favorite. Without the key and by keeping the message simple, without a lot of text, the cipher was incredibly hard to break.

Mario hadn't included the key.

Hadrian's Wall is the key, Annja told herself. She got a graph-paper pad and a pen from her backpack. Paper and pencils were still an archaeologist's best mechanical tools. But it was the mind that did the brunt of the work.

Annja checked her memory and discovered that she'd been right about the Playfair cipher. It consisted of five rows of letters by five columns of letters.

Usually a code word or phrase was written across the top, without a break and without repeating letters. X was used for the first time double letters – like EE or SS – were used. The rest of the letters were put in order from left to right, from top to bottom.

Annja wrote "HADRIAN'S WALL" down, then took out the apostrophe and the repeated letters. She was left with "HADRINSWL."

Since "WALL" had double Ls, she added an X. Her final tally was ten unique letters: "HADRINSWLX."

Once she had those, she worked swiftly, slipping the letters into the five-by-five grid. Traditionally Q wasn't used, or I and J were used in the same space. The cipher key took shape quickly.

 

H A D R I

N S W L X

B C E F G

J K M O P

T U V Y Z

 

Then she started substituting letters. The rules were simple.

Whenever letters were on the same row they were substituted for the ones immediately to their right, wrapping back around to the front of the row as needed.

If letters were in the same column, they were substituted with letters just below them, wrapping back to the top of the column if necessary.

Letters that were in different rows and columns were used as anchors to form rectangles. Then the letters in the opposite corners of the rectangles were substituted out, staying within the same row, not the same column.

The first coded message – "ESIREF" – became "CWHIFG."

Since that didn't look like any answer she recognized, Annja knew something had gone wrong. Her frustration came rushing back. The cipher idea had sounded so much like Mario, she was certain that had been the answer.

Okay, Annja thought, the answer can't be wrong. Therefore the cipher key had to be. She'd missed something. Another clue Mario had to have left.

She stood up from the table and stepped back from the mosaic. What else had been hidden? She knew it had to be on the back of the mosaic.

Or on the front.

She was just about to give up and flip the tiles back over when she noticed a faded line made up of discolored stones. Taking the mini-Maglite she habitually carried from the backpack, she shone the light on the tiles, exploring the discoloration more closely.

Upon dedicated inspection, she saw that the stones had been intentionally discolored. A gentle wash of some kind of stain had lent them a faint yellowish tinge.

At first she'd thought there were only ten discolored tessera. The correlation between the number of tiles and the number of unique letters in the code word didn't escape her.

In the end, she saw that there were twenty-five discolored tiles. The discoloration on fifteen others was less, but it was still there. Not only that, but they were laid out in a five-by-five square.

The center nine tiles were discolored the same shade. That shade matched the fourth tile down in the last column.

Pulse quickening, Annja knew she was close to the answer. The letters in the code word had to be in sequential order. The only orders could be two rows of three followed by a row of four.

Or Mario had begun on the outside and worked his way into a spiral.

"Yes," Annja whispered as she put pen to paper on a clean page.