Go inside the preps for the show that airs live Wednesday night at 8 p.m. ET/PT on NBC.
NBC's Hairspray Live! is broadcasting, well, live, on Wednesday night, and stars Ariana Grande and Kristin Chenoweth tell ET the musical's message of acceptance might be more needed now than it was 28 years ago.
"It's more prevalent and more relevant than ever before," Chenoweth says.
Chenoweth, 48, plays Velma Von Tussle while Grande, 23, plays Penny Pingleton -- a role she obsessed over growing up.
"This was always the role that I sang along to," Grande reveals. "She's always been my favorite role, I think. I naturally gravitate towards quirkier, nerdier, weirder characters. But the thing about her that I've been raving about all day is that she has this big, beautiful, evolved brain for the time that she grew up in, and her mama is not having it. It's beautiful because you know she never learned to hate or to judge or differentiate and I love that."
The musical, based on John Waters' 1988 film of the same name, follows young ingénue Tracy Turnblad as she chases her dream of appearing on a popular TV dance show. The character, originally played by Ricki Lake, was inspirational for many due to her full-figured body type, which hadn't typically been seen in a leading lady role.
"You don't think of a 200-pound girl being the ingenue and selling it and getting the guy, so it really did open every door for me," Lake told ET last month. "It gave me this crazy career I've had for almost 30 years."
The show's focus on race and diversity adds to the timely feel, especially considering the setting. Turnblad is a resident of Baltimore, where Freddie Gray died in police custody last year.
But the show does an excellent job of remaining upbeat and fun while tapping into serious themes and pressing the need for inclusion.
Grande, Chenoweth, Derek Hough, Jennifer Hudson, Martin Short, Harvey Fierstein and newcomer Maddie Baillio (who plays Turnblad) will dance and sing for about 500 live audience members during the lively production.
WATCH: The 'Hairspray Live!' Cast Just Did the Most Epic Mannequin Challenge Ever
It's been such a happy experience for Grande that she broke down in tears on Tuesday night at the prospect of the project coming to an end.
"It's tomorrow night and I'm already crying," the "Dangerous Woman" singer is heard telling Hough in an Instagram video.
"I came out to the hall jokin' around and this sweet lil' soul was feeling emotional about this amazing journey ending," the Dancing With the Stars pro captioned the video. "Such a pleasure sharing this experience with you @arianagrande #tomorrowistheday #hairspraylive #newfriends #newfamily #grandelove."
Hairspray Live! airs Wednesday at 8 p.m. ET/PT on NBC.