It wasn't a job that Eric O'Neill set out to do. But the 27-year-old was tapped for an assignment that would bring down perhaps the most damaging spy in U.S. history — Robert Hanssen.
When he first applied to the FBI, he was too young to become a special agent. So instead he trained to be an undercover surveillance specialist. O'Neill was trained to watch, photograph and follow any target considered a threat to national security. "We would call ourselves ghosts," he said, "because you're following someone without being seen."
O'Neill was just out of college, and newly married. He was trying to finish law school at night, and his day job as an FBI "ghost" seemed exciting. Then he was mysteriously re-assigned, and got a call from his boss on a Saturday morning.
O'Neill's supervisor drove out to his home to talk with him. When his boss arrived, he wouldn't even talk to O'Neill inside the house. The two went outside and talked in the car, for security reasons.
At the time, the FBI's then director, Louis Freeh believed that Hanssen had sold reams of secrets to the Russians, including the names of American spies, causing at least two to be executed.
O'Neill had never heard of Hanssen, but he jumped at the assignment when his boss asked if he would help catch him.
Although O'Neill was not even a full-fledged special agent of the FBI, he was chosen for a few special qualities he had. "I was Catholic and that was extremely important to Hanssen," O'Neill said, "Secondly I was male. I also knew a lot about computers."
Other than those key qualities, it was no secret that O'Neill was completely unqualified to go up against Hanssen. "There were a number of people who said if anything is going to screw this case up, it's him, because he's not trained undercover, he's a surveillance operative," O'Neill said.
On his first day in FBI headquarters, he almost proved all of his critics right. O'Neill said, "I'm thinking I'm gonna go catch the super spy," O'Neill said and then, "I get lost."
The FBI's plan was both counter-intuitive and bold. If Hanssen had access to some of the FBI's secrets and was selling them to the Russians, the FBI would create a new job just for him, and give him access to almost all the FBI secrets and then watch his every move. Part of that involved O'Neill. An FBI spokesman told 20/20 O'Neill played a small role in the case, but the bureau declined to let other agents involved in the case be interviewed.
For about six weeks, O'Neill says, they worked together in room 9930 of FBI headquarters. According to O'Neill, on his very first day, Hanssen called him in to teach him his first lesson about spies, describing something he called "Hanssen's Law."
According to O'Neill, Hanssen said the spy is always "where he has access to the information that he knows he can use to do the most damage and get the most money. And he knows how to use it and get away with it."
O'Neill said, "I really felt at that minute that he was saying, if you're onto me then try and catch me because I'm better than you and all these guys at the FBI. Because I'm the great Robert Hanssen."
O'Neill's would also see a different side of Robert Hanssen. We now know that Hanssen reportedly had an obsession with Internet pornography and dated and lavished gifts upon a stripper who told us they never had sex. But, according to O'Neill, the senior agent was a very weird guy to share an office with.
O'Neill recalled one instance when Hanssen asked him to come into his office and see a computer program he had downloaded from the NSA [National Security Agency] Web site. "While he was showing me this," O'Neill said, "I notice that he's physically excited."
O'Neill said he reported this strange behavior to his bosses, but it didn't really advance the case. They needed to know when and where Hanssen would make his next "drop" of secrets to the Russians.
O'Neill said his colleagues found materials that suggested Hanssen was preparing to do a "drop." The signs were there: chalk to leave a mark telling the Russians the drop was made and plastic bags to protect the documents where they were hidden outdoors. So, O'Neill was given an objective: get Hanssen's Palm Pilot.
O'Neill said the FBI believed that getting access to Hanssen's Palm Pilot was critical to learning about Hanssen's contacts with the Russians. However, according to O'Neill, Hanssen almost never let it out of his sight. So a plan was developed.
Hanssen's bosses would surprise him in his office and invite him to go shooting with them in the basement firing range. That created an opportunity; leaving O'Neill alone and with access to Hanssen's office.
O'Neill said Hanssen was agitated and cursing under his breath as he headed for the range with his bosses. Then, O'Neill received an "all clear" message on his pager. He ran into Hanssen's office unzipped Hanssen's bag, grabbed the palm pilot and data card and ran down one floor to have the information downloaded onto a computer.
It was a good plan until Hanssen abruptly cut the target practice short after just a few minutes. O'Neill received another page indicating that Hanssen was probably returning to his office.
As the data on Hanssen's palm pilot was downloading to a computer, he was on his way back. The download was going slowly, because, according to O'Neill, Hanssen had encrypted the data on his Palm Pilot.
For the FBI, the Palm Pilot was the jackpot. Hanssen had kept copies of the documents he had given his Russian contacts on his palm pilot, and he also had stored a "drop date" on it, according to O'Neill.
The drop would be the smoking gun. Hanssen was followed to a Virginia park, where he allegedly left another packet of classified material, which was then intercepted by the FBI.
The double agent surrendered without a fight. He was arrested, charged with espionage and treason. To avoid a possible death penalty, he pleaded guilty and is now serving a life sentence.
O'Neill, who has not spoken to Hanssen since, said, "If they let him watch 20/20 in prison that I was the one who helped bring him down … he will feel so betrayed."
O'Neill said he thinks Hanssen had no idea about the operation to catch him. "In the end he might say 'I knew all along,' because of his ego," O'Neill said, "but I truly think … he had no idea he was under surveillance, particularly throughout everyday that a ghost was on him."