Two thousand is the number of Democratic House and Senate staffers invited to a screening of the undercover videos of Planned Parenthood officials discussing the sale of fetal tissues and organs.

Sixteen is the number of congressional aides who responded to the invitation, sent out by the anti-abortion group Susan B. Anthony List.

Seven is the number of staffers who actually checked in at the event’s registration desk on Capitol Hill Thursday morning.

Two is the number who stayed through to the end of the 90-minute program.

SBA List President Marjorie Dannenfelser said she wasn’t surprised.

“Horror is hard to look at,” she said to a room mostly filled with reporters and representatives from her organization, plus one staff member from the office of Majority Whip Steve Scalise, R-La., who reserved the conference room at the group’s request.

From graphic images of dismembered fetuses to blunt descriptions of abortion procedures, Dannenfelser said, “there are a lot of people who really have to look in the face of this horror.”

But it turns out a lot of people already have — even Democrats, who have been accused by Republicans of blindly sticking to abortion rights talking points without watching the footage that’s become a catalyst for congressional hearings and a movement to defund Planned Parenthood.

One staffer who stayed for the duration of the screening — Randy Abreu, a law clerk for House Judiciary ranking member John Conyers Jr. of Michigan — said this was his third time watching the series of videos (another Conyers aide arrived late and left early, but wouldn’t comment on why he’d attended).

Two aides for Sen. Richard Blumenthal, D-Conn., walked out partway through because, a Blumenthal spokesman later told CQ Roll Call, they discovered they had already seen what was being screened and didn’t need to sit through a rerun.

There are nearly 40 hours of purportedly unedited footage from the hidden cameras during the lengthy sting operation of Planned Parenthood by the anti-abortion Center for Medical Progress, but the videos that have gone “viral” over the past few months are heavily edited.

Supporters say the edits were done merely for length, while critics argue it is a manipulation of the facts. They say Planned Parenthood donates fetal parts for research with the consent of mothers and only requires payment for transport.

Amy Kelbick, a senior policy adviser to Rep. Jan Schakowsky, D-Ill., walked out before the screening began. Schakowsky’s spokesman later said it was because Kelbick had also already watched the edited films and didn’t have anything to gain from watching them again.

Meanwhile, the progressive lawmaker’s office is among those urging a Justice Department criminal investigation into whether the Center for Medical Progress obtained the Planned Parenthood footage illegally.

But Kelbick did not slip out of the room quietly as others had.

Just as Dannenfelser was just beginning to speak, Kelbick raised her hand and said she wanted to know whether the unedited videos would be shown. Dannenfelser said she wouldn’t indulge the interruptions and said Kelbick would be asked to leave if she didn’t quiet down.

When Kelbick was finally told the edited videos were queued up, she stood up and left, followed by aides for California Reps. Judy Chu and Grace Napolitano. Dannenfelser chided Kelbick for creating a scene that took attention away from the subject at hand as reporters followed the staffers out of the room for interviews and photographs.

Dannenfelser said it would take far too long to show all the unedited videos, and reiterated what she said in her invitation: Anyone who wanted to watch the full footage on their own would be empowered to do so.

Staffers and reporters were offered the chance to have a personal screening at SBA List headquarters, and representatives from the group also, as promised, passed out bundles of DVD copies of the full footage to take home after the event.

However, some confusion led to the disks being assembled incorrectly, with CQ Roll Call for instance walking away with 10 copies of “PP Video # 4.”

Kelbick, incidentally, took 10 copies of “PP Video # 3.”