NBC took a chance when it decided to air The Sound of Music Live, a televised live performance of the classic musical, back in 2013. But it turned out to be an incredible ratings hit, thereby spawning several reiterations. But some of you may find yourselves wondering: is the Hairspray Live! cast really singing? Based on the format of the live musicals, it would be a safe assumption to say that they are. Considering the fact that they're also dancing around the entire time, this is more impressive than you might think.
It's common knowledge that pop stars and other performers often lip sync their songs when performing live because it is so hard to be running around while also trying to sound as good as they did in the studio. Musical theater performers, on the other hand, sing live during their performances. While most film adaptations of musicals have the actors pre-record the songs and then lip sync when filming, it's a whole different ball game with this kind of performance. While it is technically a filmed production, the idea behind it is that it is a "live" performance. This would imply that the performers will be putting on the sort of live entertainment one might see on Broadway, which means they will be actually singing.
This, however, does not account for the fact that some of the actors may cheat, à la Britney Spears, and pretend to be singing live while they actually recorded the song weeks ago. Because it is televised, there is some other movie magic which could be happening behind the scenes that we don't know about. While a stage production has to run through the whole thing in order for every performance, it's possible that the scenes from Hairspray Live! could be shot out of order the way a movie is, or that some scenes may require multiple takes to get it quite right.
What we do know for sure is that those will be the actual voices of the people performing — and there are some powerhouses in the cast for sure. Ariana Grande and Jennifer Hudson, for starters, will be starring, and they are both more than capable of singing just about anything and having it sound amazing. Whatever the format is, I cannot wait until this show makes its grand debut!