It looks like any other date: A couple shares a romantic meal in the course of getting to know one another.
Hilarie, a 28-year-old attorney, uses words like perceptive, hard-nosed and skeptical to describe herself. She's focused, curious and outgoing.
Tony, a 32-year-old software engineer, describes himself as fair, sensible and rational. He's also focused, curious and outgoing. That's according to an exhaustive, 320-question self-evaluation that both Hilarie Link and Tony Bako have filled out to join eHarmony, the online dating service that paired them.
It looks like any other first date -- except Hilarie and Tony's rendezvous is being watched over by multiple cameras and a Ph.D. in relationship studies.
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The Ph.D. is Gian Gonzaga, who conducts research for eHarmony. Hilarie and Tony have agreed to the strange setup to test the company's ability to match people.
"They seem[ed] to fit very well," Gonzaga said of the couple's eHarmony profiles. "There are a couple of things in there that are special highlights for them in terms of their personalities, which tend to indicate that they might have some things in common that really drive the getting-more-connected in a relationship."
The computer matchup was being put to the test over dinner.
"He shows a lot of gestures with his hands, and they'll also move into leaning in and out toward each other as the conversation goes on," observed Gonzaga. "All of those things are indications of the emotional connection between the two of them."
eHarmony claims it is responsible for 236 marriages a day -- marriages that have already produced 100,000 babies in this country, the company says.
eHarmony: Is There a Formula for Love?
eHarmony CEO Greg Waldorf showed "Nightline" some of those happy newlyweds plastered along a wall at the company's headquarters. All of the relationships were born of a secret computer algorithm that matches people.
"I've talked to many of our success couples and, frankly, some of them are my friends," said Waldorf. "One of my closest friends from school got married to his wife through eHarmony. When I went to their wedding and said I'm the CEO of eHarmony, a woman said to me, 'Do you go to every wedding?'"
But how does one capture the intangible chemistry of a true love connection in an algorithm or a formula?
"I think of our algorithm as a starting point," said Waldorf. "It's a way to say to the user, 'Here are a whole bunch of matches that you're compatible with.' I wouldn't presume to tell anybody that I know exactly which user they're going to be interested in. We're giving them a really good set of users to start with, and then it flips to that very personal approach of, 'Wow, I think I have something in common with this person.'"
eHarmony: The Joy of Cancellation
Waldorf says eHarmony is different from other online services because it's not in the dating game but in the business of long-term relationships.
It is a business with a huge pool of customers.
eHarmony's call center measures success in a way that would make most company's cringe: by cancellations.
"We appreciate you and once again, thanks again for trying out our service," operator Joe Sebo was saying when "Nightline" paid a visit to the call center. "And congratulations."
Sebo explained what had happened.
"Essentially, a caller was just calling in to report a success story and to get their account closed with us," he said. "Whenever a customer has found the love of their life on our service ... essentially they call and report the story. ... They're always really excited."
Waldorf said his goal is to reach America's 90 million eligible single people, many of whom he says are lacking only one thing: hope.
Waldorf believes the company's big brain -- the group of Ph.D.s who write the algorithm that's supposed to put people together -- makes all the difference between this place and just another dating service.
"The Ph.D.s are a special breed, they have expertise in everything from psychology, how do relationships get formed, all the way through from computer science and mathematics to really figure out the complexity of the massive scale of our system, how to make it all happen in a very predictable way for the user, knowing we have a lot of choices that we can make to which choices we can deliver."
What does he say to the skeptics who think there's no mathematical formula for love?
"I would say to anyone who is skeptical, go talk to our success couples."
It turns out that even the so-called "success couples" started as skeptics.
"To be perfectly honest, I thought it was kind of weird to meet someone online," said Obed Varela, who has been happily married to Jennifer Sandoval, whom he met on eHarmony, for three years. "It's hard enough to meet people in real life, so [I was] not at all a believer." The couple has one baby, with another on the way.
"[It's] nothing short of a miracle, honestly," said Varela.
In a room wired with cameras, Gonzaga studies couples' interactions to find out more about what makes a healthy relationship. He gathers data that helps tweak the company's method of putting people together.
"This is one of the things that we are looking for when they are talking about the initial stages of their relationship," Gonzaga observed. "Couples that end up referring to the other person and then to the dyad more than they do to themselves, that's an indicator that they're more focused on the relationship."
Back at the restaurant, dinner was over.
The couple said eHarmony had worked for them.
But to cut to the chase: Were they headed for marriage?
"I think so," Tony stammered. "I mean, I don't, maybe, I hope so -- hopefully ... I don't want to say."
Hilarie, meanwhile, was nodding yes.
"Maybe I shouldn't be nodding yes," she said.
"No, I hope so, it's going great," said Tony. "I'll say yeah, I love her and I can't imagine being with anybody else at this point, so I would say definitely yeah."
They say love comes in many forms. eHarmony's version starts with a line of computer code and doesn't always work.
But sometimes it all adds up.