Once again, Detectives Rizzoli and Frost have invaded my studio, and this time they’ve brought along a well-dressed black gentleman whose soft-spoken diffidence indicates that he is not a policeman like them. The sudden interruption startles my class, and the dozen students stand frozen, their sparring exercises abruptly halted. Only Bella strides into action, slipping past the students to plant herself beside me. She acts as my fierce guardian, all five foot, four inches of her, including her spiky black hair. I am not surprised to see the visitors, and I cast a glance at Bella that says: Stand down. Allow me to deal with this.

She gives the subtlest of nods but stubbornly remains at my side.

Detective Rizzoli assumes command of the conversation. Of course she would; she wears her authority like a coat of armor. “We understand you’re in possession of an antique sword, Mrs. Fang,” she says. “We ask you to surrender it to us now.”

I look at Detective Frost. It is a cold stare of accusation, and shame darkens his eyes. On the night we shared dinner, the night that a friendship warmed between us, I allowed him to hold Zheng Yi and I shared the sword’s history with him. That night, I saw kindness in his face. Now that face tightens into a mask that closes off any hint of our earlier connection. It is clear that he is a policeman above all, which poisons any possibility of friendship between us.

“If you choose not to hand over the weapon,” says Detective Rizzoli, “we have a search warrant.”

“And if I give you my sword, what will you do with it?” I ask.

“Examine it.”

“Why?”

“To determine if it was used in the commission of a crime.”

“Will it be returned to me undamaged?”

“Mrs. Fang, we’re not here to negotiate. Where is the sword?”

Bella steps forward, fury radiating off her like the hum of a high-voltage wire. “You can’t just confiscate it!”

“The law says I can.”

“Zheng Yi has been in my family for generations,” I say. “It has never left my possession.”

Detective Rizzoli frowns at me. “What is Zheng Yi?”

“The name it was given when it was forged. It means ‘justice.’ ”

“The sword has a name?”

“Why are you surprised? Don’t you have a legend in Western culture, about a sword named Excalibur?”

“Madam Fang,” says the black man, his voice quietly respectful. “Believe me, I don’t want the sword damaged in any way. I understand its value, and I promise I’ll treat it with care.”

“And why should I believe you?” I ask.

“Because it’s my job to protect and preserve such weapons. I’m Dr. Calvin Cherry from the Arthur Sackler Museum, and I’ve examined many ancient swords. I know their history. I know the battles they’ve fought.” He dips his head, a gesture of regard that impresses me. “I would be honored if you’d allow me to see Zheng Yi,” he says quietly.

I look into his soft brown eyes and see a sincerity that I did not expect. This man pronounces the name with a perfect accent, so I know he speaks Mandarin. Even more important, he understands that a fine weapon is to be revered for the skill of its craftsman, and for the centuries it has survived.

“Come with me,” I say. “Bella, please take charge of the class.”

I lead the visitors into the back room and shut the door. From my pocket I take out a key and unlock the closet to reveal the silk-wrapped bundle that lies on the shelf. With both hands, I present it to Dr. Cherry.

He receives it with a bow and carefully sets it on my desk. Detectives Rizzoli and Frost watch as he peels back the layers of red silk, exposing the sheathed weapon. He pauses for a moment to examine the scabbard, which is made of lacquered wood with bronze fittings. The handle, too, is lacquered wood, but covered with stingray skin that has been stained green. When he pulls out the sword, the blade makes a musical whine that sends a thrill across my skin.

“Liuye dao,” he says softly.

I nod. “A willow leaf saber.”

“And you say this comes from your family?”

“It was my mother’s. And before that, her mother’s.”

“How many generations does it go back?”

“All the way to General Washi.”

He looks up, clearly startled. “Truly?”

“It is our family bloodline.”

Detective Rizzoli asks, “Who was he, this general?”

“You’d appreciate this bit of history, Detective,” says Dr. Cherry. “General Washi was a woman, and the most famous of the double dao masters. A warrior who fought with two swords, one in each hand. She commanded thousands of soldiers during the Ming dynasty, leading them in charges against those Japanese pirates I told you about.” He looks at me in wonder. “And you’re her descendant.”

Smiling back at him, I nod. “I’m pleased you know of her.”

“But this is astonishing! To think—”

“Dr. Cherry,” cuts in Detective Rizzoli. “What about the sword?”

“Oh yes. Of course.” He pulls out his glasses and slips them on his nose. Behind the lenses, his brown eyes squint in concentration. “This has the typical curve of a willow leaf dao. It’s a very old design,” he explains to the two detectives. “This one is somewhat shorter than usual, but I guess you’d expect it if this weapon was designed specifically for a woman’s hand. These blood grooves here are also typical, meant to make the blade a little lighter. Look at these etchings in the steel! I’m amazed how deep they still are! And this grip, you’d almost think it was original, if you didn’t know it has to be at least five hundred …” He pauses. Above his spectacles, I can see his frown deepen. For the next few moments he says nothing at all. He brings the dao close to his glasses, minutely studying the cutting edge of the blade. He tests the flexibility. Finally, he reaches into his pocket for a magnifier, through which he examines the etched panels.

At last he straightens, and when he looks at me, I see a strange sadness in his eyes. A look that is almost regretful. Quietly, he slides the dao back into the scabbard and holds it out to me. “Madam Fang,” he says. “Thank you for allowing me to see Zheng Yi.”

“Then you are finished with her?” I ask.

“There’s no need for us to take it after all.”

Detective Rizzoli protests, “Dr. Cherry, the crime lab needs to examine it.”

“Trust me, this is not the weapon you’re looking for.”

Rizzoli turns to Detective Frost. “Is it the same sword you saw?”

Frost looks confused. His gaze flicks up and down, between my face and the sheathed sword that I am holding. His face deepens to scarlet as he realizes he may have made a mistake.

“Well, is it?” she asks again.

Frost shakes his head. “I’m not sure. I mean, I only saw the sword for a moment.”

“Detective Frost,” I say coldly, “the next time you visit, I hope you’ll be courteous enough to tell me what it is you really want from me.”

My barb finds its mark, and he flinches as though stung.

Detective Rizzoli sighs. “Mrs. Fang, regardless of what Dr. Cherry says, we still need to take the sword for further study.” She holds out her hands, waiting for me to surrender the prize.

After a pause, I place it in her hands. “I expect it returned to me undamaged.”

As the visitors leave, I see Detective Frost cast a regretful look back, but I wear my disdain like a shield, deflecting any apology. His shoulders are drooping as he walks out the door.

“Sifu?” Bella says softly, stepping into my office.

In the next room, the students continue sparring and kicking, grunting and sweating. She closes the door so they cannot see the look of satisfaction that passes between us.

Move, countermove. The chess game continues, and the police are still one step behind us.