Olivia Wilde learned a valuable lesson about Justin Bieber fans: Don't talk smack about the most-followed person on Twitter.
"The Incredible Burt Wonderstone" actress, who appeared on "The Tonight Show" Tuesday, unleashed a tweet March 2 after photos surfaced documenting the pop star walking around shirtless in frigid London, which kicked off his very, very bad London trip.
"Bieber, put your ... shirt on. (unless you lost all your shirts in a fire in which case my condolences and please purchase a new shirt.)," she tweeted.
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Cue the wrath of the Beliebers.
Wilde previously told CNN about her reaction to the backlash, which she called "the most hilarious thing" that has ever happened to her: "I'm going to get attacked with acid. Someone's going to throw acid in my face," she joked, comparing Bieber fans to the Bolshoi ballet incident.
Wilde, 29, who is engaged to funny man Jason Sudeikis, was simply making a joke "with love. I said it with love," she told Leno, treating Bieber the same way she would treat her little brother if she saw him without a shirt.
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"But I have to tell you, Jay, what happened was I think people misunderstood, thought I was mean-spirited and didn't realize it was said with love," the actress said. "And I got a lot of interesting feedback from his fans."
"Like how many people responded?" asked Leno, who had apparently recovered from the pretty girl fever he experienced with Halle Berry the night before.
"About 35 million people," she deadpanned, "And they had some really great notes. At first I thought they were being mean but then I realized it's just helpful advice, like friendly advice I gave to him."
That's a good sport. Here are some of those notes, per Wilde:
"'Are you a lesbian or are you too old?'" she read, "And it's great because it's a question I'd never asked myself before and I was wondering am I too old to be a lesbian? Because I did just have a birthday so I may have missed my window ..."
And another: " 'Put your shirt over you mouth,' which I'm assuming is a Shakespearean insult, so I thought that was useful for future arguments," she added. "There's about 17,000 others but they have too many expletives to say on your show."
Wilde also discussed her private karaoke sessions with her fiance and her film costarring Steve Carrell, Jim Carrey and Steve Buscemi, which opens this week. But sadly, as usual, Bieber trumps all.
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