LONDON — Game of Thrones filming has started up again, cast sightings in Belfast have peaked, and speculation about what's in store for Season 7 is quickly gathering momentum.

We already know that British legend Jim Broadbent will have a role in the next Season, but — as usual — showrunners are keeping tight-lipped about new characters and plot-lines at this early stage.

Still, that doesn't mean we can't speculate.

Introducing Devin Oliver, the singer for American band "I See Stars."

Haven't taken a selfie of the long ass blonde locks in a while // 🤘🏻 A photo posted by Treehouse (@devinoliveriss) on Aug 30, 2016 at 11:42pm PDT

Remind you of anyone?

A few days ago, Oliver shared the following, cryptic post on Instagram.

I may or may not have made an appearance in Game Of Thrones season 7 🙊 📷 @leaborama A photo posted by Treehouse (@devinoliveriss) on Sep 23, 2016 at 8:47am PDT

Hmm.

It wasn't long before the speculation started.

The Instagram post eventually made its way to the r/gameofthrones subreddit, where the speculation reached fever-pitch.

So, is Devin Oliver going to be playing Rhaegar Targaryen — ie. Daenerys' deceased older brother — in Season 7?

Well, despite the fact that he's a singer rather than an actor, it's always possible. As many people pointed out on Reddit, we know from the books that Rhaegar enjoyed singing, and — given the Season 6 flashback that all but confirmed the R + L = J theory — it wouldn't be a surprise if we were to see more of Jon Snow's real dad in the coming season.

Game of Thrones has a history of casting relatively unknown actors, too, so Oliver's lack of IMDb credits wouldn't necessarily be an obstacle.

Also, he really does look the part.

That one time I was on mars but really it's just Detroit A photo posted by Treehouse (@devinoliveriss) on Sep 19, 2016 at 10:23am PDT

Still, nothing is confirmed at this stage.

Oliver might be joking, or he might simply be in Season 7 in a much minor role.

Mashable has reached out to HBO for comment and we will update this article if we receive a response.

UPDATE: Sept. 29, 2016, 5:33 p.m. BST A spokesperson from HBO told Mashable they don't comment on casting speculation.

Bonus: Game of Thrones cast blows up social media with Season 7 news