MOSCOW — Sergei V. Skripal was a little fish.
This is how British officials now describe Mr. Skripal, a Russian intelligence officer they recruited as a spy in the mid-1990s.
When the Russians caught Mr. Skripal, they saw him that way, too, granting him a reduced sentence.
So did the Americans: The intelligence chief who orchestrated his release to the West in 2010 had never heard of him when he was included in a spy swap with Moscow.
But Mr. Skripal was significant in the eyes of one man — Vladimir V. Putin, an intelligence officer of the same age and training.
The two men had dedicated their lives to an intelligence war between the Soviet Union and the West.
When that war was suspended, both struggled to adapt.
One rose, and one fell.
While Mr. Skripal was trying to reinvent himself, Mr. Putin and his allies, former intelligence officers, were gathering together the strands of the old Soviet system.
Gaining power, Mr. Putin began settling scores, reserving special hatred for those who had betrayed the intelligence tribe when it was most vulnerable.
“A person who chooses this fate will regret it a thousand times,” President Vladimir V. Putin said of moles.
Six months ago, Mr. Skripal was found beside his daughter, Yulia, slumped on a bench in an English city, hallucinating and foaming at the mouth.
British intelligence chiefs claim they have identified the men as members of the same Russian military intelligence unit, the G.R.U., or Main Intelligence Directorate, where Mr. Skripal once worked.
It is unclear if Mr. Putin played a role in the poisoning of Mr. Skripal, who survived and has gone into hiding.
But dozens of interviews conducted in Britain, Russia, Spain, Estonia, the United States and the Czech Republic, as well as a review of Russian court documents, show how their lives intersected at key moments.
In 2010, when Mr. Skripal and three other convicted spies were released to the West, Mr. Putin had been watching from the sidelines with mounting fury.
Asked to comment on the freed spies, Mr. Putin publicly daydreamed about their death.
It hardly mattered that Mr. Skripal was a little fish.
A military orchestra festival last month in Red Square in Moscow.
The collapse of the Soviet Union unleashed a drive for personal enrichment.
In the late 1990s, Sergei Skripal returned from Madrid, where he was posted undercover in the office of the Russian military attaché.
Russia was in disarray.
Coal miners, soldiers and doctors had not been paid in months.
Workers took control of a St. Petersburg nuclear power plant, threatening to shut it down unless they received their back pay.
Mr. Skripal was good fun, though, happy in the company of other men.
Oleg B. Ivanov, who worked with him in the Moscow regional governor’s office, recalled him as a man struggling to keep up with changes in the country, more “Death of a Salesman” than John le Carré.
He lived in a shabby housing block in a field of identical housing blocks, drove a rattletrap Niva and told endless stories about his days as a paratrooper.
One thing didn’t fit: At restaurants, he insisted on paying for everyone.
“That was something that set him apart,” Mr. Ivanov said. “I don’t know where this came from.”
In their crowd there were many other former Soviet spies, who had devoted the first part of their life to qualifying as intelligence officers.
Now it all seemed pointless.
“You have to understand, the Soviet Union collapsed,” Mr. Ivanov said.
“All the Soviet ideology that underpinned our government also disappeared into history.
There was a slogan at that time: Enrich yourselves.”
That was Mr. Skripal’s story, he said: Always looking for side hustles.
“By his psychological type, he was a materialist,” Mr. Ivanov said. “He simply loved money.”
“He simply loved money,” Oleg Ivanov said of Mr. Skripal, his former colleague.
And that, he said, explained his friend’s betrayal.
In 2006, Mr. Ivanov was driving in his car when heard Mr. Skripal’s name on the news.
Prosecutors said that, while posted in Spain, Mr. Skripal had entered into a business partnership with a Spanish intelligence agent, who “bumped” him to a recruiter from Britain’s foreign intelligence service.
Mr. Skripal had been meeting his handler secretly since 1996, they said, passing on secrets in exchange for $100,000.
It was not a large amount, around $12,500 a year.
Prosecutors asked for a sentence of 15 years, five less than the maximum, and the judge reduced it to 13, because Mr. Skripal was cooperative.
Mr. Ivanov found Mr. Skripal’s betrayal, if not especially honorable, at least comprehensible.
“It was a period of building up capital,” he said. “It was affecting everyone in the government, including structures like the G.R.U.
He also came under the influence of needing to make money.
The time came.
The oath he gave to the Soviet Union — it seems to me, at least — you didn’t need to adhere to it anymore.”
Those were years of free-fall.
Who could define loyalty?
‘Moscow Is Silent’
Mr. Skripal, bottom left, at a Soviet military academy in 1975.
Vladimir V. Putin, another midcareer intelligence officer, was living through the same loss of status.
In 1990, he was sent home early from his post at K.G.B. headquarters in Dresden.
His salary had not been paid in three months and he had nowhere to live — so many spies were returning that the government could not house them.
He arrived home with nothing to show for his years abroad but some hard currency and a 20-year-old washing machine, a goodbye gift from a neighbor in East Germany.
The unraveling had felt personal for Mr. Putin, who was unable to protect all his German contacts from exposure.
One day Mr. Putin pleaded with the Soviet military command to defend the K.G.B. headquarters, which was surrounded by German protesters eager to seize files.
In a panic, they were stuffing them into a furnace.
“Moscow is silent,” an officer told him.
He would recall that phrase again and again in the years that followed.
“I had the feeling then that the country was no more,” he said later.
His friend Sergei Roldugin said he had never seen Mr. Putin so emotional as when he spoke about those East German informants whose identities had been revealed.
“He said it was equal to treason,” Mr. Roldugin told Mr. Putin’s biographer, Steven Lee Myers.
“He was very upset, extremely.”
Scores of intelligence agents turned to the West at that time, as defectors or informants, and Mr. Putin cannot speak of them without a lip curl of disgust.
They are “beasts” and “swine.”
Treachery, he told one interviewer, is the one sin he is incapable of forgiving.
It could also, he said darkly, be bad for your health.
“Traitors always meet a bad end,” he once said.
“As a rule they either die of heavy drinking or drug abuse.”
When he came to power, Mr. Putin went after traitors the same way he dealt with other ills of the chaotic 1990s, the oligarchs and crime bosses.
His first years in office were marked by a barrage of spy convictions, some clearly meant as revenge.
The tone was set around the time of Mr. Putin’s first election as president in 2000 — the day before, in fact.
That was when the Federal Security Service, which Mr. Putin had recently commanded, leaked the identity of a British MI6 officer who was a prodigious recruiter of Russian spies.
It was a careful, meticulous leak, intended to savage the man’s career, a deliberately personal attack: The spy service also revealed the officer’s wife’s name and the fact that he had two daughters.
That officer, it was later revealed, was the man who had recruited Mr. Skripal.
A Family Collapses
A family photo showing Mr. Skripal with his wife, Lyudmila, and daughter, Yulia, at a school graduation in 2001.
After Mr. Skripal was convicted in 2006, he was “untouchable,” said Mr. Ivanov, his former colleague.
The Skripal family, suddenly alone, kept their shame private.
Ivan V. Fedoseyev, 76, their next-door neighbor, noticed that Mr. Skripal was gone and assumed he had left his wife, Lyudmila, for another woman.
“It was embarrassing to ask about it,” he said.
Lyudmila ruminated bitterly about friends who had testified against her husband, said Viktoria Skripal, Mr. Skripal’s niece.
She complained to Viktoria that plenty of their G.R.U. colleagues had decided to live in the West after the Soviet collapse.
“Why has nobody called them traitors, she said,” Viktoria recalled.
By then, Mr. Putin’s Russia was in full flower.
He had brought Russia’s business tycoons to heel, and his own allies, mostly former intelligence officers from St. Petersburg, took the helm of Russia’s key industries.
Mr. Putin’s friends took their place among the world’s superrich, buying up yachts and Mayfair mansions.
But Lyudmila Skripal was reduced to begging for money.
She could no longer afford to send the monthly allotment that her husband needed in prison, for food and toiletries, so she asked that his mother’s pension, roughly $500 or $600 a month, be diverted to him, Viktoria Skripal said.
In sheaves of legal appeals, she begged a long list of Russian military officials — the defense minister himself, finally — to restore her husband’s pension.
“I am forced to appeal to you for help due to the difficult situation that I, a pensioner, find myself in at the current time,” she wrote.
For her efforts, over two years, she was awarded 33,148 rubles and 89 kopeks, which at the time was worth about $1,000.
Viktoria Skripal, Mr. Skripal’s niece, said that his family suffered greatly while he was in prison
She had stopped taking care of herself.
The family’s apartment was falling apart, the walls warped and the linoleum stained, said Lilia Borisovna, who bought the apartment later.
“The apartment was decaying,” she said.
So was Mrs. Skripal’s body.
She was experiencing symptoms of endometrial cancer, as it metastasized, untreated, from her womb to other parts of her body.
It was clear something serious was wrong, and Viktoria Skripal urged her to seek medical help.
But Mrs. Skripal refused to see a doctor, she said, “until Sergei Viktorovich came home.”
Mr. Skripal was trying to get out of prison early and submitted a detailed appeal to a military court.
In his trial, he had confessed to passing classified information to a British intelligence officer. But in his appeal, according to court papers, he said he had mistaken the officer for a businessman who “simply made him an offer to come work for his firm abroad after his retirement from diplomatic service.”
The appeals court did not buy it.
While the Skripals waited, their son, Sasha, was slipping into a deep hole. Much of his life had been built around his father’s G.R.U. contacts: His wife, Natalya, was the daughter of another colonel who lived in the same complex. His job had come through the G.R.U. network. After his father’s betrayal became public, it all slipped away from him.
Sasha abruptly quit his job, Mr. Ivanov said. His father-in-law told Moskovsky Komsomolets, a Russian newspaper, that Sasha was drinking heavily and that he recommended his daughter divorce him. Sasha was treated for kidney disease and died in 2017 at the age of 43.
A Trade Is Proposed
The Federal Security Service, the successor to the Soviet-era K.G.B., in Moscow. Mr. Putin once ran the agency.
Dialing the number of his Russian counterpart from his office in Langley, Va., Leon Panetta, the director of the Central Intelligence Agency, was not feeling optimistic.
Mr. Panetta had once met Mikhail Fradkov, the head of Russia’s foreign intelligence service. They had dined together in Washington, and as the meal was wrapping up Mr. Panetta asked his companion what he thought was Russia’s biggest intelligence failure. America’s, he volunteered, was the case for invading Iraq.
Mr. Fradkov paused for a long time, then responded simply, “Penkovsky.”
Mr. Panetta was taken aback; the answer spoke volumes about the way the Russian system viewed moles. Oleg Penkovsky was a colonel in the G.R.U. who had spied for the C.I.A. and British intelligence during the 1950s and 1960s, providing information that guided the Kennedy administration during the Cuban missile crisis. He was apprehended by Soviet authorities and, it is believed, shot.
Now it was the summer of 2010, and Mr. Panetta was on the phone with Mr. Fradkov, hoping to set in motion a deal that would free another G.R.U. mole. Days earlier, the F.B.I. had executed Operation Ghost Stories, arresting 10 Russian sleeper agents, who had been operating in the United States for nearly a decade.
“These people are yours,” Mr. Panetta said he told Mr. Fradkov.
“I said, ‘Look, we’re going to prosecute them; it could be very embarrassing for you,’” Mr. Panetta recalled saying in an interview. “You’ve got three or four people who we want, and I propose that we make a trade.”
Normally, Mr. Panetta said, such an offer would have been met with denials and obfuscation. But it was the summer of 2010, and the two Cold War adversaries were enjoying a brief thaw.
Military cadets in Red Square in Moscow last month.
Mr. Putin had stepped away from the presidency, installing a faithful deputy, Dmitri A. Medvedev. It was a scheme that allowed Mr. Putin, who became prime minister, to hold onto power without violating constitutional term limits, but also a test of cooperation with the West. Mr. Medvedev had built a rapport with Barack Obama during a trip to Washington, meeting for cheeseburgers at a hole-in-the-wall diner called Ray’s Hell Burger.
After the phone call with Mr. Panetta, the Russians agreed to a swap. Mr. Panetta gave Russia four names, including Mr. Skripal’s.
“I think it was our Russia people at the C.I.A. who came up with his name,” Mr. Panetta said. “And he was added to the list.”
On a hot July day, guards at Correctional Colony No. 5 in the Russian Republic of Mordovia came to Mr. Skripal’s cell and told him to gather his things. He was taken to Moscow’s Lefortovo prison, where he met briefly with his family before being loaded onto a small Yak plane belonging to Russia’s Ministry of Emergency Situations. With him were three other former prisoners. All were silent for the three-hour flight to Vienna.
The mood was much different aboard the United States government-chartered Vision Airlines 737 sent to retrieve the four men. After takeoff federal agents popped champagne bottles and poured whiskey to toast the men’s freedom, according to someone present on the flight. One former K.G.B. major gave a boisterous speech. They were free.
‘Have to Hide Their Whole Lives’
Mr. Putin with Dmitri A. Medvedev.
He was displeased by Russia’s thaw with the United States during Mr. Medvedev’s presidency.
One man, however, was stewing.
“A person gives over his whole life for his homeland and then some bastard comes along and betrays such people,” Mr. Putin, practically snarling, said when asked to comment about the swap on live television.
“How will he be able to look into the eyes of his children, the pig.
Whatever they got in exchange for it, those 30 pieces of silver they were given, they will choke on them.
Even if they didn’t die, he added, they would suffer.
“They will have to hide their whole lives,” Mr. Putin said.
“With no ability to speak with other people, with their loved ones.”
Then he stiffened his back, squared his shoulders and spoke straight to the camera.
“You know,” he concluded, “a person who chooses this fate will regret it a thousand times.”
Did he know the names of the traitors who had betrayed their comrades, a journalist had asked him shortly after the swap.
“Of course,” Mr. Putin said.
Would he punish them? Wrong question, Mr. Putin replied mysteriously.
“This can’t be decided at a press conference,” he said.
“They live by their own rules, and these rules are well known by everyone in the intelligence services.”
Mr. Putin was becoming impatient with Mr. Medvedev’s cooperation with Mr. Obama.
In 2011, he erupted over the French-led bombing campaign in Libya, blaming Mr. Medvedev for yielding to American pressure and failing to use Russia’s veto power at the United Nations Security Council to stop it.
His livid criticism of that campaign, which he likened to a “medieval call to a crusade,” presaged what happened next: He took back power in 2012, and set about undoing every element of Mr. Medvedev’s little thaw.
But Mr. Skripal and the other traitors, delivered into the hands of Western intelligence agencies, had already scattered.
Lonely in Exile
Surveillance footage of Mr. Skripal in a convenience store the month before he was poisoned in Salisbury, England.
It was hard to miss Mr. Skripal in Salisbury. Matthew Dean, the head of Salisbury’s City Council, recalled spotting him one day in the Railway Social Club, a modest establishment with electronic poker machines and framed prints of racehorses.
Mr. Dean is a pub owner, familiar with Salisbury’s categories of drinkers. This one did not belong.
“It was a Sunday afternoon, and he was drinking neat vodka,” Mr. Dean recalled.
“He was extremely loud, and he was wearing a white track suit.
I remember saying, ‘Good God, who is this person?’
And they told me he was their only Russian customer.”
Mr. Skripal tiptoed around the question of his past, at least at the beginning.
In an English-as-a-second-language class at Wiltshire College, he introduced himself as the head of a construction company, recently arrived from Spain. Ivan Bombarov, a Bulgarian cabdriver who had friends in the same class, said they all smirked about his cover story.
“We in Bulgaria, we see a lot of mafia guys,” he said.
“We was like, ‘Yeah, whatever.’”
Mr. Skripal’s solitude deepened after Lydumila died of cancer in 2012, two years and three months after the swap.
In 2017, Sasha died, collapsing on a weekend trip to St. Petersburg.
His last family member, Yulia, was back in Moscow with her boyfriend.
Last year, he struck up a conversation with a Russian émigré couple at a grocery store in London, and startled them by entreating them — perfect strangers — to come visit him in Salisbury.
As he described the deaths of his wife and son, his eyes filled with tears, said the businessman, Valery Morozov.
“He missed Russia,” said Ross Cassidy, a burly former submariner who became one of his closest friends.
Lisa Carey, another neighbor, observed the Russian on his daily rounds, walking to the Bargain Stop in his tracksuit to buy scratch tickets.
“He used to boast about being a spy, and we would all laugh at him,” she said. “We thought he was mental.”
He did have secrets, though. Mr. Skripal traveled regularly on classified assignments organized by MI6, offering briefings on the G.R.U. to European and American intelligence services.
Such assignments may be devised as a way to keep a former spy busy, said Nigel West, a British intelligence historian.
It is not unusual, he said, for defectors to feel bored and underappreciated, something he called “post-usefulness syndrome.”
“Case officers are very aware of it,” Mr. West said.
“When the time comes, and they say ‘Don’t call me, I’ll call you,’ you may well say, ‘I’ve got something very interesting to do.’
That’s what tends to happen. Their status has been slightly exaggerated and enhanced, and they start swallowing their own bathwater.”
Contacts with fellow intelligence officers took him back to the old days.
He made repeated visits to consult with the CNI, the spy service in Spain.
He traveled to Estonia and the Czech Republic, among other places.
“Basically they were meetings of people from the same field who used to sit on opposite sides,” said a European intelligence official, speaking on the condition of anonymity to characterize Mr. Skripal’s 2012 visit to Prague.
“They had lunch together. It lasted for hours. It was great fun.”
The British government, which helped arrange Mr. Skripal’s assignments, has said nothing about them, and British espionage experts shrug them off as unremarkable lectures.
But it remains unclear what information Mr. Skripal was passing on.
And Russian officials may have been more judgmental than their British colleagues suspected, said Aleksei A. Venediktov, editor in chief of the Moscow radio station Ekho Moskvy, which has reported extensively on the case.
“When you’re over there, you do not work against us, that’s the rule,” Mr. Venediktov said.
“It’s not written anywhere, but it’s known.
You were pardoned for your past and in the future, live on your pension, grow flowers, calm and quiet.
These are the conditions.
You do not use your military skills against Russia, against the Soviet Union.
What did Skripal do?
It’s confirmed, he violated that rule.”
Two Trips From Moscow
Yulia Skripal had something important to do in England.
Yulia Skripal in May, after recovering from the poisoning.
She had sold her father’s old apartment, together with the old furniture and the double-headed eagle, the symbol of Russia, that he hung on the wall.
She bought herself a small place in western Moscow.
But recently she had cleared out to make way for workers to start renovations.
The key change was a tiny room that Yulia wanted redecorated, so it could be used as a nursery, according to Diana Petik, whom Ms. Skripal hired to oversee the renovations.
Yulia, she said, was planning to marry her long-term boyfriend and become a mother.
But there was one thing she felt she had to do first.
Mr. Skripal could not safely travel to Russia for the wedding, so she wanted to at least have his blessing.
This was her intention, Ms. Petik said, when she buckled herself into a seat on an Aeroflot flight bound for London on March 3.
A day earlier, according to British authorities, two Russian intelligence officers arrived in London aboard a different Aeroflot flight.
They were inconspicuous, dressed like Russian provincials in parkas and tennis shoes.
In one of their bags was a specially made bottle, disguised as a vial of Nina Ricci’s Premier Jour perfume, loaded with a military grade nerve agent.
A bottle disguised as a vial of Nina Ricci’s Premier Jour perfume, loaded with a military grade nerve agent. CreditLondon Metropolitan Police
As Yulia Skripal went through customs at Heathrow Airport and waited for her luggage, the two men, according to British investigators, were already in Salisbury, carrying out surveillance ahead of the attack.
The next afternoon, shortly after 4 p.m., a woman named Freya Church was leaving her job, at a gym called Snap Fitness, when she came across two figures slumped on a bench in the picturesque center of Salisbury.
The woman was leaning against the man.
The man was gazing up at the sky, as if he saw something there, making strange, jerky movements with his hands, she told the BBC.
By that time the two men were boarding a train at Salisbury station, the first leg of their escape back to Moscow.
News of the crime would begin to ripple outward, through the intelligence services of a dozen countries, through the United Nations Security Council and the global body tasked with banning the use of chemical weapons.
For the agencies that oversee the army of spies that remained behind after the Cold War, it would throw into question every understood rule of engagement.
But for now, it was a finished job.
A middle-aged G.R.U. officer facing an uncertain future had betrayed his tribe.
In accordance with rules well known by everyone in Russia’s intelligence services, two assassins came to England and took care of a little fish.