Enjoying USA's new docuseries, Inside the FBI: New York? Good news: We've got a particularly relevant (and chilling) web exclusive clip.
Special Agent Maria Ricci discusses a case from June 2010, in which 10 Russian sleeper cells were arrested for spying on the United States.
"The Russians illegals program has been going on for over a century," Ricci says while discussing the case. "This is something that they've invested an insane amount of time, energy, and money on."
Catch the full clip below, and watch Inside the FBI Thursdays at 10 PM/9c.