David Daleiden, founder of the Center for Medical Progress, at the Value Voters Summit on Sept. 25. (Charles Ommanney/The Washington Post)

The slim young man with the Clark Kent glasses mingled easily at the conference of abortion providers. By day, he sat quietly in his company’s booth, under a sign festooned with a burbling lab flask. By night, he schmoozed with presenters at the swanky hotel bar.

If people noticed that he seemed a bit stiff, they tended to write it off as an odd physical tic. In fact, David Daleiden was probably trying to keep his hidden camera straight.

Daleiden, 26, is the anti­abortion activist who masterminded the recent undercover campaign aimed at proving that Planned Parenthood illegally sells what he calls aborted “baby body parts.” He captured intimate details of the famously guarded organization, hobnobbing at conferences so secretive that they require background checks and talking his way into a back laboratory at a Colorado clinic where he picked through the remains of aborted fetuses and displayed them luridly for the camera.

Daleiden’s videos landed like a bomb in Washington this summer, providing fodder for a crowded field of Republican presidential contenders and energizing social conservatives on Capitol Hill. They also shed harsh new light on the venerable women’s health organization, capturing officials sipping wine while joking about abortion and appearing to haggle over the price of fetal tissue.

This week, Planned Parenthood President Cecile Richards announced that the group would continue to donate tissue for medical research but would no longer accept compensation for storing and delivering the specimens. She said the organization has done nothing wrong but decided to take this step to disarm its critics.

Daleiden, characteristically, saw things in darker tones.

“It’s pretty much an admission of guilt,” he said this week.

Planned Parenthood President Cecile Richards appeared before the House Oversight Committee to defend the organization against allegations of illegally selling fetus tissues for profit. Things quickly became heated between Richards and several lawmakers. (Alice Li/The Washington Post)

Before emerging as the biggest star in the antiabortion firmament, Daleiden had long been a bit player. A Catholic and Southern California native who drives a Honda hybrid, Daleiden calls himself an investigative journalist and credits his California public school education with fomenting in him a passion for human rights.

At the conservative Values Voter Summit in Washington late last month, Daleiden wore his signature dark blazer and skinny black tie and a pair of “Nightmare Before Christmas” socks. During a break, he described himself as the result of a “crisis pregnancy,” born while his parents were in their junior year of college.

“I always grew up with the understanding that some people have kids in less than fully intended situations and there’s nothing wrong with that,” he said.

At 15, he said, he Googled images of aborted fetuses — an exploration that cemented his antiabortion views. While studying at Claremont McKenna College, he began fixating on Planned Parenthood. He got a job with Live Action, an antiabortion nonprofit group led by a fellow millennial that made its name by mounting undercover “stings” against Planned Parenthood. In 2009, Daleiden was kicked off the neighboring Pomona College campus after aggressively questioning a Planned Parenthood official who had been invited to speak.

And something else happened in college: While on assignment for a professor, Daleiden wound up at a conference on stem cell research where a presenter mentioned that the results of her work had been drawn from the brains of aborted fetuses.

“I thought, wait, did I hear that right?” he recalled.

His horror stuck with him for years, as did what he sees as a cruel paradox — that when it comes to a fetus, “its humanity isn’t considered valid, yet it’s precisely that same humanity that makes it valuable for experimentation.”

He soon began to hatch an audacious plan to infiltrate Planned Parenthood to its very senior reaches. He pulled the trigger in 2013.

Daleiden had been living in the Washington area and working with Live Action. That January, he took a road trip back to California with Rocky, his 6-foot, 30-pound black-throated monitor lizard. Along the way, he met with two of the nation’s most controversial antiabortion activists.

In Wichita he visited Troy Newman, president of Operation Rescue, who has made approving comments about violence against abortion providers though he has denounced violence himself. (Newman was recently deported from Australia over concerns that his presence there could inspire acts against medical professionals.)

Newman is one of three board members for the nonprofit Daleiden set up, the unassumingly named Center for Medical Progress. Another is Daleiden, and the third is Albin Rhomberg, who made headlines in the 1980s when he broke into the Los Angeles County coroner’s office to photograph aborted fetuses.

In an interview, Newman said he was not sure that Daleiden’s plan would work. A decade earlier, Mark Crutcher, the head of a Texas antiabortion group, had infiltrated a Planned Parenthood clinic in Kansas to prove that it was illegally selling fetal tissue. But after an investigation by ABC’s “20/20” and a congressional inquiry, the clinic was cleared of wrongdoing.

“I said, ‘We will have to deeply embed ourselves — and by we, I mean you,’ ” Newman recalled.

Daleiden then went to Dallas to meet with Crutcher, who gave him the same advice. Daleiden recalled: “He said, ‘You can’t just put on a lab coat and walk in the front door.’ ”

So Daleiden developed an elaborate ruse. He posed as Robert Daoud Sarkis, an employee of Biomax Procurement Services LLC, a fake company he concocted to serve as a front for the operation. He registered the company with the California secretary of state, set up a mock Web site and even created Facebook pages for his fake employees.

According to a lawsuit later filed by the National Abortion Federation, the company chief executive’s “likes” included Hillary Rodham Clinton, “The Rachel Maddow Show” and stem cell research.

With $120,000 raised from about 20 donors, whom Daleiden refuses to name, Daleiden spent nearly 30 months living his Sarkis persona. He and six paid actors visited clinics in Texas and Colorado; attended Planned Parenthood and National Abortion Federation conferences, signing nondisclosure agreements he would later disregard; and lunched with top Planned Parenthood officials. Daleiden even managed to speak briefly, camera running, with Richards, the group’s president.

The antiabortion group Center for Medical Progress posted a long version of the conversation between a Planned Parenthood executive and undercover actors on YouTube along with an shorter version that has been shared widely. These are excerpts of the longer version. (CenterforMedicalProgress.org)

Daleiden developed an in-depth knowledge of fetal-tissue research. On the videos, he can be heard breezily questioning whether the eyeballs in a petri dish are sufficiently developed to be useful for researchers and praising the intactness of a tiny liver.

And he sweet-talked his subjects. Monica McLemore, an abortion nurse and researcher at the University of California at San Francisco, experienced Daleiden’s charm firsthand in April during the National Abortion Federation’s annual meeting at the Hyatt Regency in Baltimore’s Inner Harbor.

McLemore said she was waiting for a friend at the hotel’s mezzanine bar when she was approached by a polite and flattering young man. He presented himself as a university postdoc and proffered some kind words about a presentation she had made. Could he buy her a glass of wine, he asked?

She agreed, and they talked. She found him elusive, but many people at abortion conferences are cagey about their work. Concerns about attracting violence are so pervasive that the conference is not widely publicized and attendees undergo background checks.

Daleiden quickly lost interest in the conversation, she recalled. He finished his beer and left. Three months later, McLemore saw him on “The O’Reilly Factor.” “That’s when I started calling my lawyers,” she said.

Alcohol played a central role in Daleiden’s project. Several of his subjects were caught talking glibly with a cold beverage in hand. Critics call it a trick to loosen tongues and elicit embarrassing jokes, but Newman has another explanation.

“We really felt as if these were troubled individuals,” he said. “They soothe their consciences with copious amounts of alcoholic beverages.”

Matthew Reeves, the National Abortion Federation’s medical director, also had an encounter with Daleiden, according to the lawsuit. He described Daleiden’s questions as “pushy” and “leading” and noted his “strange face-forward stiffness when speaking.” At the time, Reeves attributed this stiffness “to a personality quirk,” the lawsuit says, but he “now realizes [it] was because Daleiden was most likely carrying equipment and filming or recording the conversation.”

The lawsuit describes two women who attended the conference with Daleiden — actors, it turns out — wearing loose-fitting scarves that may have concealed recording equipment. And it includes photographs of Daleiden in black-framed glasses that he no longer seems to wear. Daleiden declined to say whether that was where he hid the camera.

The lawsuit seeks to have 500 hours of footage shot at two conferences turned over to the abortion federation on grounds that Daleiden signed a confidentiality agreement. A California judge has granted the organization a preliminary injunction, which for now prevents Daleiden from releasing those videos.

Daleiden estimates that about a third of his footage is now in legal limbo. But someone is watching it — the House Oversight Committee has subpoenaed the footage as part of its investigation into Planned Parenthood.

Planned Parenthood officials have long said that the organization follows all laws and that many women treasure the ability to donate tissue for life-giving research. In a letter to Congress, Richards complained that Daleiden and his Center for Medical Progress are not under the microscope.

“It is clear they acted fraudulently and unethically — and perhaps illegally,” Richards wrote. “Yet it is Planned Parenthood, not Mr. Daleiden, that is currently subject to four separate congressional investigations.”

Whatever the outcome, Daleiden’s project has already exceeded the wildest expectations of antiabortion activists. He has released 10 videos from clinic visits, Planned Parenthood meetings and lunches with executives, and put the abortion issue back on the front burner in Washington and on the presidential campaign trail.

Money, too, is pouring in for Daleiden, though he will say only that the Center for Medical Progress has managed to recoup its costs.

Daleiden often says he likes the abortion providers he met. He calls Deborah Nucatola, the Planned Parenthood medical director whose casual comments about abortion procedures were his first big get, a “friend.” (It is unlikely she feels any reciprocal warmth, considering that the National Abortion Federation says she has been the subject of online death threats. Nucatola declined to comment through a Planned Parenthood spokeswoman.)

At other times, Daleiden’s disdain for his targets is palpable. Asked by conservative talk-show host Glenn Beck whether he had ever encountered “evil,” Daleiden described a discussion with one of the few doctors in the United States who perform abortions in the third trimester.

“She wasn’t suspicious of my character. Everything was going well,” he told Beck. “We were talking and kind of joking, laughing about something. And all of a sudden she looked straight in my eyes, and I saw almost a flash of light go from one eye to the other . . . and all of a sudden her eyes looked hard and mean and aggressive, and for the first time in this entire project, I felt actually afraid.”

“On some level,” he continued, “we feel like that was the predator look or predator instinct that you see in someone who is accustomed to killing people.”

Alice Crites contributed to this report.