Preshow meeting

It's halfway through Oprah's final season and producer Leslie is tackling a big idea: happiness. "I'm producing the show called 'Are You Happy?'" she says. "Basically, it's a quiz. The audience can vote along with Oprah, and they can see how their happiness level is measured in their overall life."

During her preshow meeting with Leslie, Oprah is intrigued by the subject matter. "[Happiness] is a word that often used and, in our country, the United States, accepted as your right. People think, 'I have the right to happiness' and not understanding it's something you have to work at," Oprah says. "So I thought, 'Very interesting show idea and theme to get people to think about happiness differently.'"

In addition to booking everyday people to share their stories, Leslie has also convinced actress Goldie Hawn to agree to be Oprah's co-host for the day. "Goldie Hawn's a perfect person to co-host the show with me because she just genuinely is interested in what makes people happy," Oprah says. "There's a certain joy—which is, in my opinion—deeper than happiness that exudes from Goldie all the time."

Leslie leaves the meeting feeling encouraged. "Oprah seemed to really love the material. We were in there for an hour and a half talking about the subject," she says. "I was really happy about that, and I walked away feeling really, really good."

Leslie and Sheri in control room

Leslie left the preshow meeting feeling confident, but the morning of taping is another story. "The show is about to start and it just seemed like everybody was one step behind," she says. "Here we are scrambling with facts and figures at the very last minute. Everything has to be accurate."

Ready or not, the show must go on. "All right, let's get happy," executive producer Sheri says.

Near the top of the show, Oprah mentions Goldie's foundation and Sheri calls for B-roll videotape to play. Unfortunately, it's been left out of the script and can't be cued up. "I don't know where it is," Leslie says. "The show is just sort of getting off to a rocky start."

Oprah talks to Chandra

The show takes another turn when a guest named Candra takes her time explaining why she's never happy. "So Candra's going on a bit. And a little bit longer. And a little bit longer," Sheri says. "We have a lot more guests to get to, and we really are not going to be able to fit in a 25-minute therapy session."

Oprah also realizes this guest is stretching too long. "As I'm listening to her story I think, 'Who preinterviewed this woman?'" Oprah says. "Because in the preinterview, you should have known that this story was a far more complicated story than could fit this lighthearted moment."

After Candra, the show is now 15 minutes over schedule. "That was right off the rails," Sheri says.

Leslie in control room

Because time is running so long, other guests Leslie booked have to be cut. "In the show, we have various viewers in the audience who wrote in, and they have questions about happiness. Sheri didn't feel like we had any time to get to those, and we didn't," Leslie says. "Did I stack the deck with too many guests? Probably."

Oprah isn't happy about Leslie's overbooking. "I think it's the biggest mistake a producer can make because I'm thinking about the person who has to get cut," Oprah says. "I have been told over the years by various producers that, 'Oh, that person doesn't mind.' I know that is never true. Because if I put myself in that person's position, I would think, 'Of course I mind. I've already told my mother. I've already told my friends. I've told at least 10 people that I'm going to be on The Oprah Show.' Then how do you go back and say, 'Didn't happen, I got cut.'"

Oprah is even unhappier that a mistake like this was made in her final season. "It irritates me more the 25th season than it has in prior seasons because I figure, by 25 years, you should figure that out," Oprah says. "We've seen Leslie's other work. She's a really fine producer, but she's ultimately in charge. And some mistakes were made with this show."

Oprah, Leslie, Sheri and Tara

When the taping concludes, the show is 69 minutes long. "This show is supposed to be 42 minutes," Leslie says.

After the show, Oprah powwows with Sheri, Leslie and senior supervising producer Tara. "We have a motto in Harpo and that motto is: Feedback is your friend," Oprah says.

Watch what Oprah had to say 

Now, the tape will go into edit. "From time to time, this happens where we are enormously over. We are going to go through segment by segment and take out anything that's not interesting or exciting," Sheri says. "By the time the show airs, no one will ever know that there was a problem with this show."

Leslie says she's learned an important lesson. "I learn something new every time I produce a show. I learned what not to do and what to do," she says. "In this case, it was don't overbook. And I will not do that again."

Watch Sheri make a special Season 25 request of Oprah 

How Oprah celebrated her birthday