Like who knew what when -- about the FBI's investigation into a complaint that his biographer Paula Broadwell sent harassing emails to a woman close to Petraeus?
According to a U.S. official, it was that probe that revealed an affair between Broadwell and Petraeus.
Director of National Intelligence James Clapper learned of the investigation in a phone call from the FBI on election night. Clapper told the White House on Wednesday, according to a senior I.S. Intelligence official, but it's unclear when the f-b-i probe began.
"The FBI director had the obligation to tell the president or the National Security Council at the earliest state so it seems to be going on for several months and, yet, now it appears that they're saying that the FBI didn't realize until Election Day that General Petraeus was involved. It just doesn't add up, " said Rep. Peter King (R-NY)
Among other questions -- Why weren't key lawmakers told sooner? The House and Senate Intelligence Committees weren't informed until Friday.
"Are you going to investigate why the FBI didn't notify you before?"
"Yes, absolutely. I mean, this is something they --that could have had an effect on national security. I think we should have been told," said Sen. Dianne Feinstein (D-CA)
Not everyone on Capitol Hill was totally in the dark. House Majority Leader Eric Cantor said an FBI employee told him about Petraeus' affair and a possible security breach in October, after the investigation had begun.
a U.S. official says the general's communications were never compromised and he was never the target of the investigation .
Another issue? -- Petraeus stepped down days before he was supposed to testify before a Senate committee about the attack on the U.S. Consulate in Libya. Acting CIA director Michael Morell will testify instead, but some Republicans aren't pleased.
"At the end of the day, we need to get to the bottom of what happened in Benghazi.
I don't see how in the world can find out what happened in Benghazi if Petraeus doesn't testify, " said Sen. Lindsey Graham (R-SC)
CNN has not been able to reach Broadwell for comment.