A viral video from Taylor Swift's Eras tour stop in Madrid has fans shivering.
The Madrid concert clip shows an unknown individual dancing and vibing as the pop sensation sang.
The tape, shot high above the stage without protection, has raised concerns.
Some called the video disturbing, but others joked that Billie or Taylor's ex, Alwyn, is hiding.
Fans' videos of Swift's Delicate performance turned eerie when zoomed in to the stadium's highest point.
A lone figure stands mysteriously immobile, sometimes moving, sometimes making hand movements, far from security.
The internet is full of theories regarding this mysterious attendee.
Could a passionate superfan have ascended to high altitudes to catch a glimpse of the Fortnight singer, or is it anything else? The Madrid concert video may never be solved, but Taylor's trip in Madrid was remarkable.