The UFO was placed in Red de San Luis, at the crossing on Montera and the Gran Vía on 21 January, hidden from view under a black sheet. The structure was unveiled the following day, and remains in situ.
The object has been positioned slightly above the ground on a square patch of earth, implying that it has crash-landed. A large chunk is also missing from the structure.
Yellow tape surrounds the UFO, and it features Fox branding, as well as the #ExpedienteX hashtag, which translates to X-Files. This is accompanied by additional text, which translates to: 'The truth is still out there'.
While the six-part mini-series premieres on the Spanish channel today (26 January), the first episode in the series was premiered in the US and Canada on Sunday (24 January).
Last year saw a range of television-inspired stunts and activations, including and .
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