We were told by cinematographer Lawrence Sher said that Lady Gaga stayed in character while on set filming the new JOKER 2 - Folie á Deux, insisting she be called her character’s name, “Lee.”
Sher said that he felt he never met the real Gaga because like star Joaquin Phoenix, she was fully committed to always staying in character while on set. "I remember I didn't know Stefani at all and, strangely, I felt like I never really met her even during the makeup/hair test," Sher said.
Once he realized what she was doing, he called her “Lee,”, Harley Quinn’s nickname. Then everything changed. "From that point on it was like her whole connection changed and I was like, 'Well, alright, cool.' That's all I needed to know."