Warning: Contains spoilers for Game of Thrones Season 6.

OK, so this definitely one of the more far-fetched Game of Thrones theories you'll read this week, but bear with us.

Following the release of some preview images for Sunday's upcoming episode, eagle-eyed Redditor b_walker08 has come up with a theory about the shadowy figure looming in the background in the photo above.

Remember Syrio Florel? The badass Bravosi who taught Arya how to sword-fight back in Season 1?

Well, b_walker08 thinks the silhouetted figure in that episode 8 preview shot could be him.

Syrio Florel was last seen in Season One, Episode Eight. Image: hbo

But let's recap for a moment. Syrio Florel was last seen fending off a group of armoured knights who were attempting to take Arya captive in Season 1, episode 8.

Although he manages to comfortably dispatch the first few, his wooden sword — yep, he's so badass that he takes all of them on with no armour and just a piece of wood — eventually gets cut in half.

Arya shouts at him to run away, but he replies: "The first sword of Bravos does not run."

Crucially, the scene ends while Syrio and Meryn Trant are still circling each other — we don't see him get killed, and we never find out what happened to him.

So could he be about to make a return?

A lot of Redditors have commented on how much the silhouette looks like Syrio Florel.

Others theorised that Syrio might be a Faceless Man.

Some even thought Jaqen and Syrio could be the same person.

And the plot thickens. On Thursday, a fan tweeted the theory at Miltos Yerolemou, the actor who plays Syrio Florel — and he sent a cryptic response.

Could those emoji mean he really is returning? Do they signify Arya killing the waif in the next episode?

Who knows. The only thing we do know is that one character who we all thought was dead suddenly made a comeback in episode 7, and in the world of Westeros nothing is out of the question.

The final snippet of dialogue between Syrio and Arya, which takes place shortly before he shouts "Go" at her and she runs for safety, also seems prescient:

Syrio: "What do we say to the God of death?"

Arya: "Not today."

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