"What's the notation like?" I asked Xiao Kai later that day. Given her background, it was almost certain she played.

  She looked at me quizzically, as if I had asked her how to hold a cup. "Go notation? You mean a qípǔ? It is a diagram of the board, with each move numbered in sequence at its coordinate." She paused, a flash of understanding in her eyes as she realized I was testing her. "I can play."

  The next few days settled into a quiet, tense routine, our new courtyard a sanctuary in the sea of Chang'an. Each morning, my "brother" Xiao Qi and I, playing the parts of the clerk and his kin, would leave the house. We didn't seek work yet, but we made ourselves visible, buying groceries in the local market, frequenting a nearby teahouse for an hour, allowing the neighbors and local vendors to become accustomed to our presence. Xiao Qi was getting used to being a brother rather than a servant. He still acted as a subordinate, but closer to that of an overly respectful sibling. People probably assumed he was born to a concubine, a suspicion that was brought up to me in private but that neither of us bothered to dispel.

  My nightmares and nostalgic reminiscing took a bit of a back seat. I realized that when my mind was occupied, painful thoughts didn't bubble to the top so readily.

  Meanwhile, our "attendant" Xiao Kai remained within the courtyard walls. Initially she'd objected, but I'd managed to convince her that it'd be best to recover completely before venturing out. With the benefit of regular meals, clean water, and the profound relief of safety, a startling transformation took place. Her foot healed, the desperate look in her eyes softened, replaced by a calm intensity. Malnourished no longer, the gaunt hollows in her cheeks filled out, and a healthy color returned to her skin. The constant, subtle tension she held in her shoulders, the posture of a coiled spring ready to lash out, finally began to ease a little.

  One afternoon, as she passed through a sunbeam in the courtyard, I noted she was still slender, but it was the lean, honed physique of a lifelong martial artist, not frailty. Her face, now clean and composed, was one of striking, classical beauty, although perhaps by this era's beauty standards she was still rather thin. It might, however, be a useful trait. I wouldn't use it in some unsavory way, but it certainly adds to any narrative I'd want to weave.

  She had high cheekbones, a straight nose, almond-shaped eyes, dark and deeply intelligent. Her lips were now full and well-defined, though they'd rarely curved into a smile. Her hair was now a clean, shining curtain of black silk, tied back from her face in the simple style of a young man, a constant reminder of the role she had to play. She held herself with an air of sharp, quiet, and contained grace and insisted on wearing the attendant's coarse linens. I think it must have been something of a comfort to wear that mask.

  I didn't pack any of my drawings for this mission. If any were to get out, our cover would be blown, so instead the evenings were for Go. Here, at the board, Xiao Kai's true nature, sharpened and honed by her trauma, came roaring to the surface. She played with a fierce, almost vicious aggression. Every move was a strike, every placement an attack. Her entire strategy revolved around cutting my groups and trying to kill them in vast, sprawling battles. It was a war, a visceral re-enactment of her recent life where every encounter was a struggle for survival. The board became her battlefield, a world of heated logic where she was no longer a powerless victim but a general in command. The intense focus the game required seemed to be a balm for the chaos that had shattered her world.

  Her murderous style was utterly alien to me, and our first games were a brutal learning experience for us both. I would win a game through a strategic strangulation, only for her to win the next by overwhelming me in a complex, close-quarters fight I couldn't keep up with. We were relatively evenly matched and with every game, we grew sharper.

  One evening, I returned to the courtyard to the quiet, rhythmic click-clack of stones being placed on the board. In the soft light of the setting sun, Xiao Kai was sitting opposite a completely engrossed Xiao Qi. She was patiently pointing to a corner of the board, her voice softer than I had ever heard it. "No, you must protect this point first. It is the eye-shape. Without two eyes, your group is dead." It was the first time I had seen her volunteer as an act of instruction, and it warmed the cold corners of our strange, fragile household.

  After several days of this intense practice, I felt ready.

  For Censor Wang, I decided it was best to act as myself: Zhang Rulin, aide to Vice-Minister Feng. I spent an evening with Xiao Kai, painstakingly recreating a game record, a qípǔ, from memory. It was a landmark game from my time, a contest between the human world champion and a groundbreaking computer program. At the time, I'd become emotionally invested and the memory of its brilliance, of a human mind crushed by a machine, was the easiest to recall. To Xiao Kai, the strategy within the record was baffling, almost divine in its logic.

  She was less impressed with my brushwork. “Your writing is barely legible” She remarked as she squinted at the words while re-writing the record. “Perhaps as your scribe, I can help you with that.”

  The next day, I dispatched Xiao Qi, dressed in his attendant's outfit, to the Censor's estate with the finished scroll and a simple message: "A gift for the Censor's collection, from his humble admirer, Zhang Rulin." He took a detour to our Garden of Serene Thought residence to change before heading to the Censor's from there.

  Meanwhile, I pursued the second track. Dressed as Zhang Lin the clerk, I took my "attendant" Xiao Kai to the West Market. The headquarters of the Whirling Cloud Caravan Company was a small city unto itself, a massive, bustling compound of warehouses, stables, and offices reeking of camel, spices, and commerce.

  As promised, Toothman Yao's letter worked like a key. Steward Bahram, a sharp-eyed Sogdian with a perpetually weary expression, granted us an interview. He was impressed by my quick identification of a deliberate error in his test ledger and offered me a probationary position: junior clerk, warehouse division. The pay was modest, not that I really cared, but I was in.

  A week passed, and our new life fell into a strange rhythm. By day, I was Zhang Lin, a diligent clerk, learning the flow of goods and money and listening for any whispers of mismanagement. By night, I returned to our small courtyard to become Zhang Rulin again.

  This evening, as we returned from the market, Xiao Qi was waiting for us with a message from Censor Wang's estate. I unrolled the elegant scroll to find a diagram of a complex life-and-death Go problem, with a short, unsigned note attached: "An interesting strategy. Can your master solve this?"

  He was testing me.

  Xiao Kai and I spent the evening hunched over the board. It took the two of us together to come up with an elegant answer. I carefully diagrammed the answer, but instead of just sending that back, I prepared a counter-move. On a separate sheet, I meticulously laid out the opening moves of a modern trap, a modern AI-popularized 3x3 invasion, with the title, "The Scholar's Humble Query." The next day, I asked Xiao Qi to deliver both scrolls, the respectful answer and the confident challenge.

  My new life as Zhang Lin the clerk was a lesson in drudgery, spent with brush and abacus in a cramped office. It was painful, manual work, and I longed for the efficiency of a calculator. But my modern mind saw patterns others missed: double distributions, outliers, a certain captain whose cargo was consistently underweight, rounding errors that always favored the same supplier. Some issues I reported and earned a rapid promotion out of probation, and a modest raise to the point where I could support our modest operation without dipping into Lord Feng's operational fund.

  With some issues, however, I said nothing, but began keeping a secret ledger of my own, recording every anomaly. Xiao Kai joined me during the day after she'd recovered, dipping in and out, running her "errands."

  Two weeks passed in this manner. Our cover was established, and the threads of our investigations were slowly being gathered.

  Then, a messenger from the Censor's estate delivered another small, elegant scroll. This time, there was no puzzle. There were only four characters, written in a bold, inquisitive hand:

  "Who, sir, are you?"

  He had taken the bait.