London, July 3 : Two mysterious faceless people have been spotted in some of the UK's A-list events like Wimbledon, Henley Regatta, the Harrods sale and Elton John's White Tie and Tiara Ball.
With a membrane of skin stretched tightly over their eyes, noses and mouths, the alien-like figures were most recently snapped 'watching' a match perched on Murray Mount at Wimbledon.
Close inspection of the pictures rules out an alien invasion - small perforations around the eye areas of the masks allow the people beneath to see the world outside.
The anonymous figures have provoked much speculation among Internet bloggers, desperate to guess what they are trying to achieve.
One theory is that they are a couple of celebrities keen to avoid the glare of the paparazzi lens. Indeed, they seem to have access to some of the most sought-after A-list events.
"They probably aren't just random people off of the street. If it ends up being a pair of celebrities who have had it with being photographed all of the time and are staging a protest, I vow to support every project they appear on from now on," the Telegraph quoted a blogger, as stating.
"Whatever their purpose, I want to join them. And I have a new Halloween costume for this year," the blogger added.
Another suggestion is that they are from a group named Anonymous, which formed on the Internet and is best known for organizing protests against Scientology.
The favourite theory seems to be that they are part of a viral marketing campaign, possibly for BBC science fiction television series Dr.Who, or even - according to one internet site - for luxury car brand Lotus.
A blogger wrote: "This ad for .... the Lotus, takes the alien cake on over-the-top ads. Apparently you're a faceless droid until you ..."buy" a personality in the form of a Lotus."