Mona and the eleven maimed soldiers sat in a circle of plastic chairs in the multi-purpose room at the YMCA. A rickety fold-up table against the wall bore an empty coffee urn and a cookie tray with a grease-spotted doily. The soldiers had lost arms in conquered deserts and cities overseas; Mona had lost hers on Election Day. She'd just finished driving a bus full of middle-aged first-time voters to the high school. Police in riot gear had come to break up a group of hairy young people protesting rigged voting machines. There had been gunfire and an explosion, and she had awakened on Thursday with a headache, a blood transfusion, and a right arm that ended at the elbow. Mona was still out of breath, having dashed to the Y from her office, and her gone hand was blazing with pain, clenched as though she were trying to crush a diamond in her fist. The pain was Mona's reason for joining the soldiers in the multi-purpose room. It was an information session about an experimental therapy for hand and arm amputees with chronic pain. The only thing missing was the information.

Eventually the double door squeaked open, admitting a woman with thick tortoiseshell glasses and hair like a pile of beige feathers. She was wrangling a big box in a vinyl cover. A few soldiers rushed up to help her, but she smiled and shook her head and managed to place the box safely next to the cookie tray. Mona saw a ring on the woman's finger; it was average, a single tiny diamond in a plain gold band. Someone loves that woman, Mona thought. Someone met her at a party or a bar and he's going to marry her even though her hair looks like beige feathers. Mona didn't feel scornful or jealous. It was just an odd thing, that such an ordinary-looking person's life contained that level of passion—that there was someone who could look at this tortoiseshell-rimmed woman and see every day of his future in her.

The woman unzipped the box's vinyl cover. There were two holes on the side lined up with the table's edge, and a double-sided mirror bisected the inside of the box between the holes.

"My name's Jenny," said the woman. "You can call me Dr. Juracek, but I wish you wouldn't. I'm sure you're all wondering how that thing on the table is going to help your pain. Well, it will."

"That thing?" said a young Latino man—well built, with big shoulders and beautiful black eyes and his left forearm gone. "What do we do, look at how ugly we are until we forget how much our arms hurt?"

Jenny laughed. "OK. Who feels like their missing limb is prone to terrible cramps, and it would feel fine if you could just relax it?"

Ten of the twelve raised a hand or stump, including Mona.

"That's a common response to this kind of trauma, and it happens because the part of your brain that used to register feeling from your amputated arm went dead after you lost it. Adjacent areas of the brain dealing with sensation took over, and in the process some wires got crossed, so that instead of perceiving touch in your stump, sometimes you perceive pain, in the form of that terrible clenching sensation. And when you try to unclench it, you don't get any feedback telling you that you've succeeded—the hand's not actually there, so your motor system can't confirm it, and you can't see it, so your visual system can't either. It's the visual system we're trying to fool with this box. And I'm positive at least one of you is feeling that pain right now. So that person is going to come up here and put his arms into the mirrorbox."

No one moved.

"Come on. What are you afraid of? You've all been through emergency trauma surgery. You can handle this. Whose arm is hurting?"

Mona stood up.

"All right," said Jenny. She pulled an extra folding chair in front of the mirrorbox. "What's your name?"

"Mona."

"Mona, come sit down and put your arms in the box. Rest your elbow and your stump in the cups in front of the holes, so your forearm is all the way in." Mona sat down and did as she was told.

"Everyone, gather 'round," said Jenny. Mona heard them coming up behind her. "Look into the box."

Mona looked; so did the soldiers. She saw two arms, with identical shrapnel scars on the undersides. The reflection of her left arm perfectly matched where her gone right arm would have been. She looked whole again. She felt her throat tense up with a sob and coughed it away.

"Is this a joke?" said the Latino soldier who'd asked the question. "Are you making fun of her?"

"Of course not," said Jenny. "Mona, I need you to make a sort of conducting motion, like this, as if you were keeping time for an orchestra." Mona looked behind her to see Jenny making the motion—a symmetrical swishing gesture originating from the elbows. "Make sure you use both arms. Keep your eyes on the mirror."

"Both arms?" asked Mona.

"Trust me. Just move both arms."

Mona conducted.

It was like the arm was back. She opened both hands and felt the gone arm relax. She wiggled the fingers on both hands. She wanted to tip her head back with the relief, but remembered that she had to keep looking in the mirror to keep the pain away. She conducted some more and smiled.

"It doesn't work for everyone," said Jenny, "but I guess it works for Mona, which is wonderful. Regular therapy with this apparatus can sometimes eliminate your phantom limb permanently. There's a signup list for future sessions on the clipboard."

By the time the hour was over, the list was full.