How Barbara Walters Chose Her 'Most Fascinating' Subjects

— -- Barbara Walters previously said that last year's "Most Fascinating People" special would be her last.

However, this year's crop, including Scarlett Johansson, Neil Patrick Harris, and Oprah Winfrey, convinced her to do another.

"It really has turned out to be a sensational list," Walters told ABC News. "I'm very happy. It's a wonderful special, and the fact that we have these kinds of guests make it easy to do two hours."

Walters, who will reveal this year's Most Fascinating Person during the Dec. 14 special, made sure to curate a varied list of people, and each man or woman she interviewed surprised her in some way. Here's why each person made her list:

1. Scarlett Johansson: "What was surprising to me was that she forgot to tell me that she was married!" joked Walters, who spoke to the actress before her marriage to Romain Dauriac was made public. "But she does very few interviews, and she was extremely open." In the interview, Walters said that Johansson discusses her relationship, being a new mother, and being a sex symbol. "Her private life is very private, so we love that we could do it," she said.

2. Neil Patrick Harris: Like many people, Walters is in awe of Harris's talent and incredible work ethic. "It's such a sign of our times, the fact that Neil Patrick Harris is someone who appeals to both men and women, and is married, and has babies," she marveled. "[He and David Burtka] are today's couple... and there's nothing he can't do."

3. Chelsea Handler: Walters was impressed by the late night host's decision to leave her successful E! show, "Chelsea Lately," in favor of a new Netflix original. "She’s very funny and the fact that she’s taking a new route... [is] adventurous," she noted. In this wide-ranging interview, Walters was able to show Handler's softer side during a discussion about the comedian's late mother. "That's what you can do with these interviews if you can take the time," she explained. "You peel away the top layer, the thing that they say all the time, and you try to really find out who they are and what makes them tick."

4. David Koch: Koch, the sixth richest man in the world, never does interviews -- but he did for this. Walters was fascinated by his controversial background. "People love him or hate him," she noted. "He's huge! Koch Industries owns everything from Dixie cups to oil wells, and I was happy to talk to him."

5. Michael Strahan: Fans of "Good Morning America" and "Live with Kelly and Michael" already suspect that Strahan is a pretty happy-go-lucky guy, but Walters was able to confirm that he's "an absolutely delightful man." "There’s whole trend of big, hunky football men becoming stars and he’s the leader of the group," she said. "He was very upbeat, very easy to talk to." In spite of his past personal problems, Walters said that he radiates optimism. "He wakes up every day smiling," she said. "I don't wake up every day smiling!"

6. Taylor Swift: This year, Swift transitioned from country singer to pop star and invited her fans into her home to sample her new music -- a gesture that touched Walters. "Most stars don't want to have anything to do with their fans after they've done the performance," said Walters. "She does." During their interview, Walters was also impressed by Swift's poise. "She's very natural," she said.

7. Oprah Winfrey: This, by Walters' count, is the fifth time she's interviewed Winfrey, with each sitdown revealing something new. "We've both grown over the years," Walters said. And still, there's one thing they always bond over: Loving their careers. "Oprah and I talk very much about taking time for ourselves," she noted, "but as she said, she can't remember the last 25 years and I feel [the same]!"