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. Family Photo

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. Getty Images

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." Courtesy Jessie Gugig

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. FBI

The FBI had been watching the Guryevs for years to determine who they were working with and what their mission was. FBI

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. FBI

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. FBI

Another of the arrested spies was Anna Chapman, shown here in an FBI surveillance photo. FBI

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. US Marshal's Service

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. File/AP

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. FBI

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. FBI

CNN's original series, "Declassified," obtained this image of Semenko's Virginia driver's license from the FBI. FBI

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. FBI

Another of the ten spies was living in Boston. He went by the name Donald Howard Heathfield and held this Canadian passport. FBI

Heathfield also held this certificate of naturalization, which said he was a US citizen. FBI

Also living in Boston was Tracey Lee Ann Foley. She held this Canadian passport, which also was obtained by CNN from the FBI. FBI

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. FBI