(CNN) For unsuspecting residents of a suburban Montclair, New Jersey, neighborhood, it seemed too crazy to be believed: their quiet, unassuming neighbors had turned out to be Russian spies.

The couple, known as Richard and Cynthia Murphy, had appeared to be part of a typical American family, living in a beige, two-story colonial-style home with their two young daughters at 31 Marquette Road.

Cynthia's business card said she worked as a financial planner at an accounting company in nearby Manhattan. Richard told neighbors he was a stay-at-home dad raising Lisa, age nine, and her 11-year-old sister, Kate.

The shocking truth emerged when the FBI raided the house in 2010: Richard and Cynthia's real names were Vladimir and Lydia Guryev.

"You could have told me they were Martians from space and I would have been less surprised," said Elizabeth Lapin, a poetry professor who still lives down the street from the home now known as "the spy house."

The Guryevs had been gathering information since the 1990s for Russia's SVR, which the FBI describes as the modern equivalent of the KGB. The KGB, if you remember, was the widely feared national security agency of the now-defunct Soviet Union, tasked during the Cold War with running a domestic secret police force and operating a network of spies throughout the world.

On June 27, 2010, the FBI arrested the Guryevs along with eight other alleged Russian spies in Manhattan, Yonkers, Boston and northern Virginia. The announcement triggered headlines reminiscent of the Cold War, and even inspired the creation of FX's 1980s-era spy drama "The Americans."

Photos: The spies next door In 2010, Richard and Cynthia Murphy were raising two daughters in their two-story colonial home in Montclair, New Jersey. The FBI said they were spying for Russia. Their real names, according to the FBI, were Vladimir and Lydia Guryev. Hide Caption 1 of 19 Photos: The spies next door Her business card said she worked as a financial planner at an accounting company in nearby Manhattan. He told neighbors he was a stay-at-home dad. In June of 2010, the FBI arrested the Guryevs along with eight other accused spies scattered in Boston, Manhattan, Yonkers and Virginia. They all pleaded guilty to one count of conspiracy to act as an agent of a foreign government within the United States without notifying the US Attorney General. All ten spies and their children were transferred to Russia in an exchange for the release of four people who were "incarcerated in Russia for alleged contact with Western intelligence agencies," according to the Justice Department. Hide Caption 2 of 19 Photos: The spies next door Now, seven years later, the "house just sits there and it's empty," said Jessie Gugig, who lives just a stone's throw away. "It's just a constant reminder," Gugig said. "Nature is kind of taking the house back. Ivy is starting to eat into the house. The garden is completely overgrown." Hide Caption 3 of 19 Photos: The spies next door The Guryevs -- along with the other spies who were arrested -- held various official documents such as these passports that backed up their fake identities, the FBI said. Hide Caption 4 of 19 Photos: The spies next door The FBI had been watching the Guryevs for years to determine who they were working with and what their mission was. Hide Caption 5 of 19 Photos: The spies next door The FBI secretly searched their home and found this notebook. It helped them break the code that spies were using to communicate with Moscow. The notebook contained a strange system of numbers and letters which turned out to be computer keystrokes. After using trial and error with several combinations, investigators cracked the 27-digit password which opened messages hidden inside photographs that spies had posted online. When the FBI was able to crack the code, they could then eavesdrop on what the spies planned to do next. Hide Caption 6 of 19 Photos: The spies next door This FBI surveillance image shows Vladimir Guryev, known as Richard Murphy, to the left at a New York train station receiving a package from another Russian agent. It was part of the evidence that the FBI used as evidence against the Guryevs. Hide Caption 7 of 19 Photos: The spies next door Another of the arrested spies was Anna Chapman, shown here in an FBI surveillance photo. Hide Caption 8 of 19 Photos: The spies next door Unlike the Guryevs, Chapman was living in the United States under her real name. She had obtained British citizenship by marrying a citizen of the United Kingdom. After their divorce, Chapman kept her married name and moved to New York City, the FBI said. She was posing as a real estate agent. Hide Caption 9 of 19 Photos: The spies next door This undated file image taken from the Russian social networking website "Odnoklassniki," or Classmates, shows Chapman ironically posing in front of New York's Statue of Liberty. Hide Caption 10 of 19 Photos: The spies next door Another member of the group of ten was a man known as Juan Lazaro, who held this Peruvian passport while living in New York City. Hide Caption 11 of 19 Photos: The spies next door Mikhail Semenko was living outside Washington under his real name before he was arrested as part of the group of ten. The FBI said his background check was clean enough to allow him entry into the United States on a student visa. Nonetheless, he eventually worked as a spy for Russia, the FBI said. This snapshot shows Semenko posing in front of the White House. Hide Caption 12 of 19 Photos: The spies next door CNN's original series, "Declassified," obtained this image of Semenko's Virginia driver's license from the FBI. Hide Caption 13 of 19 Photos: The spies next door This image from an FBI video shows Semenko in a wooded area hiding a package for another spy to pick up. The video offered proof that Semenko was spying for Russia. Hide Caption 14 of 19 Photos: The spies next door Another of the ten spies was living in Boston. He went by the name Donald Howard Heathfield and held this Canadian passport. Hide Caption 15 of 19 Photos: The spies next door Heathfield also held this certificate of naturalization, which said he was a US citizen. Hide Caption 16 of 19 Photos: The spies next door Also living in Boston was Tracey Lee Ann Foley. She held this Canadian passport, which also was obtained by CNN from the FBI. Hide Caption 17 of 19 Photos: The spies next door Foley had this Massachusetts real estate broker's license, a photo of which CNN obtained from the FBI. The FBI said Heathfield and Foley created their fake identities by using birth certificates of deceased infants and then posing as those deceased people -- building identities around the documents. Hide Caption 18 of 19 Photos: The spies next door This FBI surveillance photo shows alleged Russian spy Christopher Robert Metsos in the US. Metsos is still at large, the FBI says. Hide Caption 19 of 19

But while the deep-cover Russian spies on "The Americans" "do all sorts of reckless, wild things," said neighbor Virginia Bailey, that wasn't the impression she got from the Guryevs.

"By all accounts," Bailey told CNN, "these neighbors were neither reckless nor wild."

This is what it was really like to live next door to a Russian spy, according to various Montclair residents who spoke to CNN.

Hiding in plain sight

Looking back, neighbors say the Guryevs' "spy house" was a perfect place to hide in plain sight. Manhattan was just 30 minutes away by shuttle bus. And the house property backed up against a 21-acre wildlife preserve where meetings with agents and exchanges of information could easily be hidden from prying eyes.

The family wasn't overly social -- but they weren't exactly hiding either. Neighbors say they sometimes attended summer neighborhood block parties.

Before the raid, Bailey and her daughter, Jessie Gugig, remember seeing their neighbor "Cynthia" walking her dog many mornings down Marquette Road. Although they never stopped to have a conversation, Bailey remembered her as being "very attractive and very well put together. She always dressed very nicely."

Some neighbors said the couple spoke with accents, but Lapin said she never heard one.

"The girls built a lemonade stand one summer," Lapin said. "That was such an American thing."

Lapin said she had a "premonition" that "something strange" was going on long before the raid. A few months before, she noticed unusual, prolonged construction under the neighborhood streets. The Friday before the raid, she said a police car had been parked in front of her house.

But espionage? It never occurred to her, Lapin said.

How they got caught

The FBI and CIA first learned about the collection of deep-cover SVR spies in the United States in the early 2000s. They were living as so-called "illegals," meaning they had no diplomatic protection.

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US authorities secretly surveilled all the spies for years, bugging the Guryevs' house and even secretly searching it when they weren't around. The FBI told CNN's original series "Declassifed" that the Guryevs tried so hard to blend into American society that they didn't even speak Russian inside their own home.

Eventually, the United States cracked a secret code the spies used to communicate with Moscow, allowing the FBI to learn more about the Guryevs' comings and goings. In 2009, the FBI shot video of a meeting between Vladimir and a Russian government official. Authorities decided it was time to arrest the spy ring.

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Jessie Gugig remembers being a 15-year-old experiencing the shock of watching FBI vans stop at the Guryevs' home, just a stone's throw from her own residence.

"Eventually another car pulled up and guys in suits with earpieces showed up with some papers that must have been a warrant," Gugig, now a 22-year-old law student, recalled. Agents suddenly poured into the home, turning on the lights and searching it from top to bottom.

"The house got lit up like it was Christmas," she said.

For at least a week after the raid, the press seemed to be everywhere throughout the neighborhood, said Gugig's mother Bailey. "I mean hordes of them," she said. "It was just a carnival."

Lapin gathered up enough courage to approach the house after the arrest and peer into the window. Inside she saw several items on a table — including Lisa's textbook on Chinese grammar, stacks of coins and a copy of a 1953 post-World War-II memoir, "Woman in Berlin."

On the wall next to a piano was a "beautiful painting" of a young girl, which Lapin believes was a self-portrait by Kate.

The Guryevs' two girls, Bailey said, were taken away to stay with a family friend.

What happened to the kids?

Two weeks after the FBI arrests, Moscow and Washington made a deal.

After all ten of those arrested pleaded guilty to being Russian agents, the United States agreed to transfer them to Russian custody. In exchange, Moscow agreed to release "four individuals" who were "incarcerated in Russia for alleged contact with Western intelligence agencies," the Justice Department said.

that the Guryevs' kids and all other children of the Russian agents were "repatriated." Kate and Lisa -- who were born in the United States -- eventually accompanied their parents back to Russia. US Attorney General Eric Holder told CBS' "Face the Nation" in 2010 that the Guryevs' kids and all other children of the Russian agents were "repatriated."

"That whole aspect was very sad," said Bailey. "To all of a sudden have their lives completely and utterly changed. The children didn't know Russia ... They have to leave their friends abruptly and suddenly. ... Everything would have just been so radically different."

Former FBI operative Eric O'Neill, who helped catch FBI double agent Robert Hanssen, said in 2010 that it's unusual for spies serving overseas to have children, because they could suffer from divided loyalties.

"When you're a parent, you're supposed to take care of your kids. You are supposed to put them first in your life. And a spy can't do that," O'Neill said.

Are other spies still living among us?

At the time, having Russian spies in the neighborhood felt like a weird throwback to the Cold War, neighbors said.

But now that people on Marquette Road are hearing more about heightened tensions between Russia and the United States, they say the idea of Russian spies living among Americans doesn't seem so surprising. Some of them are following the current US government investigations into Russia's meddling in the 2016 election and potential collusion with members of Donald Trump's presidential campaign.

In fact, Russian spies are ramping up their intelligence-gathering efforts inside the United States, current and former US intelligence officials told CNN this month

Former Soviet KGB spymaster Oleg Kalugin told CNN he "would not be surprised" to learn that Russia is still running illegal deep-cover spies in the United States. But he suspects these programs would be less active now than in 2010. Kalugin, who says he never ran illegal deep-cover programs, criticized them as wasteful and inefficient.

"It's risky and lonely and a really difficult job," he said.

One of the key pieces of evidence uncovered by the FBI in the 2010 case was a message Russian spymasters sent the Guryevs shortly before their arrest.

"You were sent to USA for long-term service trip," the message said. "Your education, bank accounts, car, house etc. -- all these serve one goal: fulfill your main mission, i.e. to search and develop ties in policymaking circles and send intels to C."

"C" is thought to refer to "The Center," an espionage information clearinghouse in Russia.

What's next for the 'spy house'

Built in 1950, the beige, two-story house is a typical middle class home for the area. It measures a bit more than 1,800 square feet and the county valued it this year at $425,700, according to Essex County tax records.

The 'spy house' where the Guryevs lived in 2010.

So much time has passed that "it's hard to believe it happened," said Bailey.

"Nature is kind of taking the house back," Gugig said. "Ivy is starting to eat into the house. The garden is completely overgrown."

"The house just sits there and it's empty," she added. "It's just a constant reminder."

Lapin -- who has lived near the house for 11 years -- said the neighborhood was friendlier before the raid. "I liked the neighborhood -- until this event happened," she said.

But the old vibe has slowly been coming back, she said. Several of her neighbors have left since the raid -- replaced by new residents who don't associate the house with the spies.

A local realtor said the home has recently been sold.

Perhaps a new family will move in soon, which will help Montclair close the book and move on from its connection to international espionage.