Isla Fisher has often been mistaken for fellow redhead Amy Adams, but the problem runs so deep, even Lady Gaga once confused the two of them.

Appearing on “Jimmy Kimmel Live!” Thursday, Fisher talked about her experiences being recognized as Adams.

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“I was there all fancy and dressed up at the bar and schmoozing with show-biz types, and the crowds parted and there was Lady Gaga,” Fisher said. “She’s heading right towards me and she says, ‘Thank you. Your performance in ‘American Hustle’, Amy, was…’”

The situation was made extra awkward because Fisher is such a big fan. “It’s Lady Gaga,” she said. “I love her so much, I [didn’t] want to tell her the truth. So I just gracefully thanked her [and] bowed my head.”

And things got extra weird soon after. ““I [looked] over [Gaga’s] shoulder and there’s Amy Adams walking into the party,” Fisher recalled. “So I said, ‘There’s Isla Fisher. She’s not even nominated for anything, what’s she doing here?’ ”

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Fisher also recalled another time, when she tried to secretly breastfeed her baby, and a woman with her kids got excited about seeing Adams, and even asked her to sing one of the songs from “Enchanted”.

All those stories led up to a special video Fisher made for Kimmel’s show, in which she made the differentiation clear, joking, “Amy Adams has auburn red; my hair is light auburn red,” and “Amy Adams played Susan in ‘Nocturnal Animals’. I played Laura in ‘Nocturnal Animals’.”

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