Joaquin Phoenix and Lady Gaga were at the Venice Film Festival for the premiere of Joker: Folie á Deux talking about the extreme transformations of the characters…and singing live!

During the press conference, he adorably looks over and asks her if he calls her “Gaga” or her real name, Stephanie (Germanotta)…to which she says “you can call me Stephanie”.  Phoenix assumed they would lip sync to recorded tracks, but Stephanie said they were singing live with a pianist on set!

You can see the movie October 4 in theaters and IMAX!