The action at the Beaufort polo grounds in Gloucestershire, England, on June 10 was fast-moving and full of surprises. And not just on the playing field. In fact, the real excitement came in the nearby parking area just after Prince Harry, playing for Beaufort, finished an hour-long match against a team that included his father, Prince Charles. Changing out of his polo gear, the 16-year-old prince sidled over to a group of female friends, where he began to "lark around, sitting in one of their cars to listen to music," says one on-looker. "The laughing and joking went on for around an hour. They were drinking soda like any other teenagers."

But the get-together rose to the level of spectator sport when Harry began playfully roughhousing with a young blonde girl—hoisting her over his shoulder and, at one point, planting a kiss on her cheek. "She sat in his lap as he was in the driver's seat of [a parked] VW," says an observer. "This particular girl he was paying the most attention to. And vice versa."

So who is this mystery girl? The question has all of the realm wondering. Even Fleet Street is stumped. "It doesn't mean she's his girlfriend," cautions Ingrid Seward, editor-in-chief of the British magazine Majesty. "But we may never know."

Still, all but the stuffiest royal-watchers seem to approve of Harry's puppy-love apparent. "It seems entirely appropriate at his age," says royals author Hugo Vickers. "To be encouraged, I would say."

Susan Schindehette
Nina Biddle and Simon Perry in London