'Game of Thrones' fans think this undercover cast photo could mean a big reunion

Warning: Contains possible spoilers for Game of Thrones Season 7.

LONDON — Game of Thrones Season 7 filming is well and truly underway, and — as is now tradition when it comes to what must be the world's most closely guarded show — people are doing everything they can to try and uncover exactly where the story is going.

Following the long-awaited re-union of Sansa Stark and Jon Snow last season, plus the fact that Arya has finally got her act together and returned to Westeros, many people have been speculating that there might soon be more Stark reunions on the cards.

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On Tuesday, Thrones fan site Watchers on the Wall shared an image of Maisie Williams in a makeup trailer alongside none other than her long-lost brother Bran (Isaac Hempstead Wright).

The photo appears to be part of a series of pictures snapped on location in Northern Ireland by a paparazzi photographer @PAP4U.

Unsurprisingly, the picture has drummed up quite a bit of excitement on social media.

So what does the photo actually tell us about Season 7?

The short answer is, frustratingly, very little. Although at first glance it's easy to think the two must be in a scene together, Watchers on the Wall have reported that Wright was in the process of leaving the set, while Williams appeared to be preparing for a scene when that photo was taken.

Basically, without a photo of the two of them actually acting in a scene together, it's impossible to know either way.

Does the fact they're on set at the same time mean a reunion is a possibility? Absolutely.

But only time will tell whether or not it's a certainty.

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