When "Game of Thrones" wrapped up its fifth season, HBO went into full lock-down mode for information regarding the hit show's sixth installment.

Without an official casting announcement and several main actors missing from the Comic Con panel, fans of the series have had to rely on Faceless-Men-esque sources in and around the "Thrones" crew.

One such report from Watchers on the Wall came in late Aug., and recent casting news may serve as validation, so proceed with caution.

[Spoilers and speculation lie ahead]

Citing its trusted sources, Watchers learned last month that Rory McCann was in Belfast apparently to film for season six. McCann portrayed Sandor Clegane, better known as The Hound, who was left for dead at the end of season four.

Death or certain death is not final in "Thrones" (remember this guy?), so it is entirely possible that The Hound would return, especially given this popular book theory. But even still, for this scenario to work "Thrones" would need at least one new character.

The first casting call Watchers obtained called for a "Priest" who is "a gruff ex-soldier" with a "no-nonsense" personality. If this is Septon Meribald, then The Hound is likely to return.

"Thrones" has also cast two acclaimed actors in "mystery roles" and the first casting was Ian McShane, who Watchers recently learned would not play Randyll Tarly, the general of Mace Tyrell's army. Watchers also learned McShane will appear in one episode and will have "a scene" with a band of outlaws described in the second casting call the website obtained.

The second "mystery role" actor is Richard Grant, who officially joined the "Thrones" cast Tuesday, HBO confirmed through Entertainment Weekly. If McShane is Meribald, it is possible Grant will be the Elder Brother.

In George R.R. Martin's A Song of Ice and Fire novels, the Elder Brother is the man who would have revived The Hound physically and spiritually, if he did in fact survive. Grant and McShane appear to have short-lived, significant roles that do not end in death.

The return of The Hound already has the makings of an episode's final scene of a mid-season episode.

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