Thing is, it turns out she knows very little about the heartthrob One Direction singer. Not even that he was from England.
What followed was an off-the-cuff interview that likely amused Wiig and entertained Fallon more than some of his viewers. The actress gave up her personal interview time and donned a spot-on floppy wig and a white V-neck T-shirt, layered on a bunch of necklaces on top and wore the 20-year-old's signature fitted black blazer, skinny jeans and boots -- boots she seemed fascinated by when she first sat down for the interview.
"Your accent is different in person," Fallon said. "Because you know, you're not from America."
"I'm from … England!" she replied, but only when Fallon said England first.
Fallon, who has been entertaining A-listers since premiering the show Monday, did know a thing or two about Styles and proceeded to inquire about his background and how the ultra-successful One Direction formed. ("The X Factor" is the answer we're looking for here).
"Uh, we were at school," the 40-year-old funnywoman said. "And it was one of those like, 'Hey, I sing,' and everyone was kind of like, 'Let's go to Harry's house and start rehearsing' and then we sent a tape, um, to RCA. And they called my house. I wrote my number... well, it was in England so it was very long. And they said, 'Do you wanna be on our record label?'"
Fallon struggled through the questions, then learned that the floppy-haired singer achieved his signature mop when he aimed two hair dryers at each other. Then Fallon asked how the band got its name.
"That's a good question," Wiig laughed. "Because we just feel like we just want to, like, sing about positive things and just keep everything moving forward. I mean I've said this like a lot in other interviews before."
In the "rapid-fire round" of questioning, Fallon lost it when Wiig answered that Styles' favorite food was carnitas.
So to really put Wiig-as-Styles to the test, Fallon asked her to sing the band's hit song "What Makes You Beautiful." A song she clearly had never heard of -- even with cue cards. Watch the clip above and see how she does.
Styles, who is quite active on social media, has yet to acknowledge Wiig's performance online.
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