The 'Game of Thrones' cast were "smothered in blankets" when they travelled to set every day.
The fantasy drama series came to an end after eight seasons at the weekend and Isaac Hempstead Wright - who plays newly-crowned king Bran the Broken - has revealed the lengths producers went to in order to keep plot details under wraps during filming.
He said: "The phenomenon of 'Thrones' is not something I am ever likely to experience again in my life. The level of hysteria and speculation around it is unprecedented.
"When we shot those final scenes of the Starks on the bay in King's Landing, we were told not to leave our hotel room in Croatia for fear of giving something away.
"When we got into the cars to go to set, we were smothered in blankets to obscure our faces and costumes."
And that's not all, as network HBO went to the expense of hiring out every room that had any sort of view of the sets, and all the cast members were accompanied by security guards.
He continued in an article for The Hollywood Reporter: "HBO also booked out every single room with a possible view of what we were shooting so that nobody could take any covert photographs.
"We were also accompanied by a top security guard who arranged every move we made as though we were Secret Service agents on some mission abroad. Sometimes you had to remind yourself that this is only a TV show."
The 20-year-old actor also confirmed that cast members who didn't even appear in the final scenes were flown out to Spain to fuel inaccurate speculation about the episode.
He wrote: "We spent five days shooting in Seville for the Dragonpit scene, which was a fairly spectacular way to wrap up our time on the show.
"Several other actors who were not even in the scene were flown over to throw paparazzi off the scent, and they were pretty grateful for their free holiday while we shot under the unrelenting sun."
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