She didn't wear this on The Tube. - Samir Hussein/WireImage
"I met Rihanna on my way home, told her she was crazy for taking the Tube," a passenger named Lisa O'Keefe was quoted as saying. "'She said, 'Dunno how you guys do it.'... She was lovely and chatty but I wasn't quick enough for a snap with her. I had to double look, her accent was more of a giveaway."
The Standard managed to get its hands on a shot of RiRi posing with a fan and looking low-key (yet barely incognito) in a white top, black sunglasses and headwrap.
It was a cool thing to do -- but not entirely original. (The Famous shall never tire of "Celebrities Riding The Subway" photos.)
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