Rihanna stunned Tube passengers on Wednesday night - when she took the Underground to get to her own concert.
The singer caused astonishment by travelling to London's O2 Arena on the Jubilee underground line, even using her Oyster travel card, The Sun said.
A source told the newspaper: "Fans couldn't believe they were sharing a carriage with a world famous pop star.
"She was just like any other passenger, except accompanied by a huge entourage. She was happy to pose for snaps and talk about the gig. She was so down-to-earth."
Rihanna got off the packed train at North Greenwich station, and jumped into a waiting car which drove her just 100 yards to the backstage area of the venue.
The Umbrella singer, who recently got into trouble with a farmer by removing her clothes in his field while filming a pop video, was more conservatively dressed on the Tube journey.
The star, who is playing 10 concerts at the arena, tweeted about her London shows: "I been waitin 4 this all year."