When Jill Kelley became concerned about the e-mails she was getting, she turned to a friend at the FBI.
That move has put the Tampa FBI office in the middle of one of the nation's biggest scandals.
What the FBI discovered is that anonymous threatening emails appeared to be coming from Paula Broadwell, Petraeus' mistress and his biographer.
The theory is she got jealous because she thought Kelley was having a relationship with Petraeus too.
The FBI here in Tampa and in Washington D.C. will not comment about it.
But the Wall Street Journal is reporting that the agent sent a photo of himself, without his shirt on, to Jill Kelley. The two apparently had a friendship that started before the threatening e-mails came to light.
Kelley turned to him for help, and he reportedly took a personal interest in the case -- too personal, even obsessive. He was pulled off the case and is now the subject of an investigation by the Office of Professional Responsibility, which is internal affairs for the FBI.
The cybercrime unit at the FBI field office in Tampa took over. This agent is not part of that unit. But, sources say he kept trying to stick his nose in it, and the rules are clear -- agents are not allowed to take a personal interest in a case.
The question now is whether the case involves a potential threat to national security.
We talked with Joe Navarro about that. He is a former FBI agent who specialized in counter-terrorism.
"If I was a hostile intelligence service, I would want to target General Petraeus, but who would I do that with? Not directly, I would do it with the people around him," Navarro said.
Navarro calls the affair an "exploitable weakness," and that's what concerns him. He says it is likely what concerns the FBI and explains why the agency is involved.
Navarro worked for the FBI for 25 years and says he never saw anything close to this story in his time -- bizarre is the only way he can describe it.