Despite the fact that Lady Gaga has won five GRAMMYs, achieved international superstardom, and revolutionized the term "pop star," the 29-year-old still experienced a severe case of nerves on her first day of filming American Horror Story: Hotel.
"I threw up on the way [to set]," Gaga recently admitted to ET in between shooting scenes for the popular FX series. "In a Ziploc bag. In my Rolls-Royce." Mother Monster then burst into a fit of giggles, adding: "I don't know why I thought that was funny, but it's funny!"
While her first day on set is a notorious one -- executive producer Ryan Murphypreviously said that she showed up “wearing diamond pasties, a Band-Aid on her hoo-ha, heels, and a black veil that Alexander McQueen made for her on the day before his death” -- no one could have imagined that she’d turn her bag of bile into a good luck charm. Or give it to her new boss!
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"I threw up in the Ziploc bag and I saved it and I brought it to Ryan Murphy," American Horror Story’s newest leading lady said. On Hotel, Gaga plays The Countess, the cold, calculated and blood-thirsty vampiress of the Hotel Cortez.
When pressed for Murphy's reaction to the unique gift, Gaga dipped into her best impersonation of the AHS creator. "He was like, 'Oh you think you can disgust me? You cant!'" she said. "The thing is, you think you can't get anything past him, but then he met me."
As if pasties and vomit weren’t enough, Gaga’s frenzied first day also included a run-in with head lice.
"One of the kids had lice the first day, so they had to shut down the set, but it was my first scene," she explained. "So I was talking to the kid, but it was actually a 40-year-old woman on her knees with a blonde wig on pretending to be the kid."
"And I was like, 'I've never done this before!'" Gaga laughed. "The camera is on me, Ryan Murphy is screaming, 'Yasss Queen!' and I'm just really praying that I don’t f**k this up."
"It was very nerve-wracking," she added.
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Since that memorable first day, Gaga has developed a unique daily exercise that she uses to step into her sinister on-screen persona. “I spend a lot of time thinking like her," the blonde beauty explained.
"When I go out, if I'm walking down the street -- which is very rare alone -- but if I'm out at a restaurant, or if I'm in the car, or I'm driving past people, I'll sort of look at them and I'll go, 'Gee, I wonder if you're clean?'" she said slyly, mimicking her on-screen counterpart.
"'I wonder if I were to kill you, if it were to be worth it for me,'" Gaga continued. "And you just have to kind of start thinking like that in a totally practical way."
Gaga stressed that her ultimate fear is for the role of The Countess to come off as a "campy blonde" or "just a bitch with the great outfits," so she often stays up all night with her scripts studying each of her lines meticulously in order to deliver a top-notch performance.
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"You'd better believe that I prepared my ass off to come in with these fantastically talented actors," Gaga said with a laugh. "All I have is my preparation time and Jesus, really to save me from possibly screwing this up."
"That's all I have when I get in there is my discipline," she explained. "That's the thing that I've learned over the past couple of years is probably my biggest strength."
American Horror Story: Hotel airs Wednesdays at 10 p.m. ET/PT on FX.
Watch Lady Gaga and fiance Taylor Kinney pack on the PDA at the AHS: Hotel premiere in the video below.