AceShowbiz - Joaquin Phoenix, returning as Arthur Fleck/Joker in Todd Phillips' musical sequel "Joker: Folie a Deux" shared a memorable anecdote involving his co-star Lady GaGa, who plays Lee/Harley Quinn. Recalling their initial interaction, Phoenix said, "I do seem to remember her spitting up coffee the first time I sang, so that felt good, that was exciting, and made me feel confident."

The Oscar-winning actor and Grammy-winning singer collaborated to create a distinct musical rhythm between their characters. "GaGa was always very encouraging of just, 'Go with what you feel, it's fine,' " Phoenix revealed.

Phoenix emphasized the authenticity of Arthur Fleck's singing voice. "It was important to protect that with poor phrasing and occasional bum notes. He's not a singer, and he shouldn't sound like a professional singer. He should sound like somebody that's taking a shower and just bursts out into song."

Meanwhile, GaGa explained that she adopted a different vocal approach for her portrayal of Harley Quinn. "People know me by my stage name, Lady GaGa, right? That's me as that performer, but that is not what this movie is; I'm playing a character. So I worked a lot on the way that I sang to come from Lee, and to not come from me as a performer."

"Joker: Folie a Deux", scheduled to hit theaters on October 4, follows the misadventures of Arthur Fleck after meeting Harley Quinn while incarcerated in Arkham State Hospital.