[Rex Features/Sipa Press] - Click image to enlarge.

They say that a picture speaks a thousand words and this one certainly does. Taking a break from shooting what appears to be a possible Vogue cover, Mario Testino (left) helped out a Keira Knightley fan by taking a picture of him with the actress using a mobile camera phone.

The star-spotting took place outside a restaurant in Berlin, where Knightley and Testino appear to be engaged in some sort of Vogue activity. How do we know this? Because our fellow bloggers has cleverly spotted Grace Coddington, creative director of Vogue US, in the background.

Meanwhile, Variety is reporting that Knightley is in talks to play Eliza Doolittle in an upcoming film remake of My Fair Lady. I hope she brushes up on her singing lessons!