LOS ANGELES •It was a cliffhanger unparalleled since "who shot J.R.?", but 10 months of agony were finally over on Sunday when Game Of Thrones returned for its sixth season premiere to reveal the fate of Jon Snow.

Viewers last saw the Lord Commander on Season 5, stabbed and bleeding on the snow. It seems like he never left, what with the various rumours and sightings, reports about haircuts and breathless dispatches about Snow star Kit Harington's romance with the equally dead, in Thrones' terms, Rose Leslie.

(Spoiler ahead) But there he was on Sunday, stone dead and stiffening, the opener appearing to answer one of the most hotly debated questions in modern television history: "Is Jon Snow dead?"

As well as revealing his fate, the series writers hit viewers with a huge curve ball that had them rushing to social media to voice their shock.

On Twitter, #GameOfThrones was the top-trending hashtag worldwide for hours before and after the HBO premiere on the United States east coast.

Fans speculated whether the sixth season opener's title, The Red Woman, indicated that the Red Priestess Melisandre (Carice van Houten) would have a hand in bringing Snow back to life.

Instead, the title was a reference to a big reveal in the last moments of the episode. "Almost that time!" tweeted football star and Thrones fans Duane Brown as the episode was about to begin, before adding an hour later: "What. The. Hell?"

"Back to the good ol' Sunday night ritual of sitting quietly for an hour and then suddenly yelling out 'NOOOOOOOO,'" tweeted New York-based fan Alex Lauer.

Game Of Thrones, which has more than 20 million viewers an episode, tells the story of noble families vying for control of the Iron Throne, all the while keeping one eye on the White Walkers leading hordes of the undead towards an invasion from the North.

The Red Woman picked up from where the Season 5 finale left off, with Sansa and Theon on the run from the Boltons, Snow's body not yet cold and Daenerys Targaryen facing the Dothraki horde that picked her up at the end of Season 5.

Everyone involved in the production had insisted Snow is definitely, irreversibly dead, but conversation among fans has focused on how, rather than whether, he will be resurrected.

Elsewhere in the fictional land of Westeros, there was plenty of blood, with Ellaria Sand and co-conspirators killing Prince Doran and his heir Trystane Martell, while in King's Landing, Cersei Lannister mourned her murdered daughter, another victim of the Sand Snakes.

Back at the Wall, Castle Black was in disarray with members of the Night's Watch still loyal to Snow preparing bloody vengeance.

The episode was mistakenly made available online for a few hours on Sunday, according to online fan forums.

Many dismissed the leak as a hoax, but a number of fans seemingly managed to watch it and posted accurate plot spoilers and screen grabs on a Reddit thread and on the Internet Movie Database.

AGENCE FRANCE-PRESSE, NEW YORK TIMES