New York, New York June 2, 11:25 AM

"It is said that a diplomat is someone who is able to deceive his friends but never his enemies."

Douglas Flannery brushed windblown strands of gray hair from in front of his sunglasses as he looked up at the speaker. The sixty-two-year-old former ambassador was sitting on a bench near South Street Seaport, watching the late-morning sun play on the East River, mesmerized by the shards of light leaping and stabbing constantly as water taxis and ferries shot by. He was thinking back to the last time he had sat beside a river, waiting for her. It was on the older, western right bank of the Dnieper River, in a park with winter-bared trees and lean squirrels emboldened by hunger. There were squirrels here, too, but they were well fed.

He stared briefly at the woman who had spoken, took her in with surprising equanimity — surprising, given how they had parted — before turning back toward the hypnotic water. She looked well, and he was glad of that; but it was the woman's accent that had stirred an immediate and overpowering rise of emotions. The inflection was Ukrainian, starting far back in the throat and possessing a somewhat nasal quality. It was an accent Flannery had grown accustomed to during the eight years in which he served as the United States ambassador in Kiev. Though he was fluent in the language — he held a master's degree in translation from NYU — he had never quite mastered a precise accent, since most of his contacts had been in writing.

"I have heard that said," Flannery replied. "Which is why, after thirty-plus years, I've learned that a good diplomat treats everyone equally — as a potential adversary."

"Even an old friend and ally?" "Everyone," he said, his body tensing, the word sounding harsher than he had intended. He relaxed his shoulders. The conflict in Crimea had done that to all of them — made them callous, or worse.

"I see," the woman replied quietly.

"Events change us, alliances challenge us," Flannery said in an apologetic tone. "In our work, 'old' doesn't mean settled. You still have to start over again."

"What is the saying? 'Everything old is new again'?"

Flannery nodded and took another look at the familiar figure as she sat easily on the opposite end of the bench. The woman was in her late thirties. She had dark eyes, a long neck, and a broad, open face framed by black hair worn in twin ponytails. Her powder-blue jogging suit was speckled with perspiration. Swallowing a mouthful of water, she began to text as she spoke.

"I suppose even friends and allies want something, often without knowing it," she said.

"Inevitably," he agreed. "Though I continue to believe that there may be rare exceptions. People who just want to say hello or reconnect. Otherwise, I might become a cynic."

She gave him a sidelong look. "You know what I remember best, Douglas? I remember watching you with the Australian ambassador when he called after Malaysia Airlines Flight 17 was shot down. So many of his countrymen lost, and you could not have been more sincerely compassionate. You will always be a humanist."

"That was three years ago, another life," he said. He met her glance, and then they both looked away.

In 2011, three years before the hostilities began in Crimea, Galina Petrenko — who had been relocated at age two from Chernivitz after the Chernobyl nuclear disaster — had secured a mission position as an ADC, an arrivals and departures coordinator who helped orient and acclimate American staff. Flannery had been impressed by her work ethic, her patriotism, and her courage: after two years at the embassy she had been drafted, but was turned down when a medical exam revealed Stage 1 thyroid cancer. She went back to the mission, missing only a few days of work to undergo treatment. Risking her job and her freedom, Galina had spied on her employers to transmit any potentially useful scrap of information to the ZSU, the Zbroyni Syly Ukrayiny — the Ukrainian military. Flannery was forced to have her dismissed, though he checked on her through mutual acquaintances. He heard that she had gone to work for a lieutenant general at the Sluzhba Zovnishn'oyi Rozvidky Ukrayiny, the Foreign Intelligence Service, and was now working as a translator for the Permanent Mission of Ukraine to the United Nations. He was not surprised to hear from her after his appointment as a fellow of the York Organization for Peace had been announced two weeks before. The think tank was located on Pearl Street, in a three-story-tall manor-style building from the Revolutionary era. Financed by wealthy Eastern European expatriates, York was deeply involved in analyzing and guiding the politics of the region.

"How is your health?" Flannery asked.

"Two years without remission, three to go," she said. A brow went up. "Unless you're referring to something else?"

"I meant the ..." He touched his throat as if he were loath to say the word. "Though there is a rumor that you are involved with Russians here," he added. "Buying information?"

"We buy from them, they buy from us — it is an honest arrangement, no one is deceived," she said.

"That also lets you watch each other," Flannery noted.

"Yes, which is why I asked you to meet me on the river," she said. "A short walk from your office but a decent run for me, and it will take a monitor at least another ten minutes to catch up."

Flannery made a point of not looking north. It would indicate a level of confidence that could put him in jeopardy. "Do you have any backup?" he asked.

"Not today. He is pursuing his own contacts."

Flannery felt an old, familiar feeling. The Galina he once knew — warm, smart, attentive — was still very much in evidence, though those qualities had a newly burnished edge. They were not enough to be off-putting, but they were enough to make him wary.

"So what do you want, Galina? I'm due back at a symposium at noon."

"For lunch?"

"For peace."

"Most of the people are there for the free food," she said. "You know, Douglas, I never knew which you disliked more in Kiev, the borscht or the small talk."

"Neither. As much as I dislike a slow verbal massage like the one I'm getting now," he said. "You and I did not part on the best of terms, but I always appreciated your directness."

"Fair enough," she replied, setting her smartphone in her lap and taking another swallow of water before continuing. "I phoned, Douglas, because we need someone inside Suhoputnye Voyska Rossiyskoy Federatsii. Our people undercover in the Kremlin have disappeared amid rumors that six armored columns are being readied as the spearhead for a renewed invasion force. The ZSU wants information on the tanks and their deployment to make a preemptive strike."

Flannery turned to her abruptly. "You want to attack Russian troops and tanks in Russia?"

"We don't want them setting a foot deeper in our soil," she replied.

"How — where have you been preparing for this?" the diplomat asked. As far as he knew, his own nation's Department of Defense was unaware of any such preparations.

"Do you really want to know?" she asked.

"If I'm to believe you, yes," he replied.

"All right. It's very ingenious," she said. "We use VRS in a secret facility. Only a handful of...