Justin Bieber started it by wearing a T-shirt of Tiffani Thiessen's '90s character, Kelly Kapowski, to Canada's MuchMusic Awards.
"I got calls from a million people last Sunday that Justin Bieber wore a T-shirt with my image," Thiessen tells Zap2it. "I thought it would be a funny back-at-cha moment if I got a T-shirt and wore it to a premiere."
So Thiessen donned a Bieber shirt, the one sold on seemingly every corner in Manhattan, and wore it to the New York premiere of "Horrible Bosses."
For the record, "Saved by the Bell" ran from 1989 until 1993, and Bieber was born a year later.
Thiessen, who is currently on USA's "White Collar," says she is a fan of Bieber.
"He is adorable," she says. "And his girlfriend ( Selena Gomez) is adorable. He could not be cuter."
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