Season 25 wouldn't be complete without Liza with a 'Z'! "Liza Minnelli is not just a celebrity. Liza Minnelli is a legend," Oprah says. "So when a legend is coming to the building, the energy of everybody is infused by that legendary status." 

Watch producer Jack, executive producer Sheri and Oprah's pre-show meeting

Jack's co-producer Bridgette has her hands full after she's assigned to work directly with Liza. "Growing up, my mom was a huge Liza fan, so Liza's been somebody who has been in my life in terms of musically and her movies," she says. "So to work with Liza was like the best thing ever."