And it's Fisher in Wedding Crashers, not Amy Adams.
While it seems perfectly reasonable to mix up the two redheaded bombshells – they have a similar look, they're two years apart in age – Adams is 39 and Fisher is 37 – and an inch apart in height – Adams says she doesn't understand why there's any confusion.
"I get Isla Fisher all the time, still. And I know Isla, and for a while our kids went to the same dance school. When I'm with Isla, we both look at one another and … I get it but I don't get it," the actress tells Vanity Fair in their January cover story.
"But just like I tell her, it could be a lot worse. I could be mistaken for a lot worse people."
Here's a helpful hint: Adams is the one starring alongside Bradley Cooper and Christian Bale in American Hustle, out in theaters Dec. 13.