Just unsure of what this is. To those that understand, awesome.
But I read "Katy in..." I expect the real Katy Perry. lol
I think I see what you mean now - I've known a version of this on German TV for many years, it's old:
Young people who are more or less talented as singers dress up for a show as their fave star and pretend to be her/him. It's a competition like in X factor, only with the difference that they're so obsessed with wanting to 'be' that one person.
What the girls in the blue wigs do here is the quality you mostly get, but the third one has really impressed me because I sing that song but couldn't get anywhere close to her technically, haha.