And here we go!
The opening is made by... Frank Underwood.
(Or at least a montage of the character dubbed by one of the show's impersonators talking about what's coming and doing some jokes about the contestants, who are going to be on Big Brother-in-law and about Marcelo Tinelli)
And then is the classic formal opening with a combination of different musicals, including Dracula, Peter Pan, Franciscus and the Cirque Du Soleil.
EDIT: Mora Godoy danced tango on an aerial platform next to Buenos Aires' Obelisco. And three kids troupes danced at the same time inside the studio, outside the studio building and in the Obelisco.
Now Marcelo Tinelli has entered and greet everybody with his classic salute "¡Buenas noches, América!" (Good night, America!)