It's not due to hit our TV screens until 2019.

But Game Of Thrones fans were pleasantly surprised to learn that the cast are already back on set, shooting the eighth and final season of the HBO fantasy series.

The revelation came in the form of an Instagram post from one of the leading stars of the show, Lena Headey, in hair and make-up, trying on wigs and fake teeth an and captioning the snap with the words 'season eight'.

'Hair and Teeth!' Lena Headey excited fans as she posted a photo of her on set of Game Of Thrones in the special effects department... seemingly confirming filming of season eight has begun

'Season8... Hair and Teeth... HAIR AND TEETH!!!' she wrote excitably, alongside a photo of her alongside Kev Alexander, the hair designer on all seasons of Game Of Thrones and Candice Banks, one of the show's make-up artists.

This comes as co-star Emilia Clarke posted a similar snap from the hair department of the show, showing off her icy blonde locks that she's required to have for her role as Mother of Dragons Daenerys Targaryen.

Grinning in the photo and also tagging the same hair stylists that Lena tagged, she posted: 'AAAAHHHHHHH SHHHHIIIII****** I done did it. Mother of dragons meet Emilia. Emilia meet mother of dragons. If you squint just so you might never know. All hail to the magnificence of @kevalexanderhair and @candicebanks74 the genius creators of 'KHALEESI WIG' (and not forgetting all the hair on game of thrones for 8 glorious years) for at long last making this magical moment a reality #khaleesikicksoff #gameofthrones #cominghomeneverfeltsogood.'

Back on set: Emilia Clarke posted a similar snap from the hair department of the show, showing off her icy blonde locks that she's required to have for her role as Mother of Dragons Daenerys Targaryen

All made up: Lena is preparing to reprise her role as Cersei Lannister in the final season

Ice ice baby: Daenerys Targaryen requires long icy locks for her scenes on Game Of Thrones

Fans are desperately and patiently waiting for the final season of the show to find out what will happen at the end.

And actor John Bradley, who plays the role of Maester Samwell Tarly, has assured that each of the six episodes of season eight will be treated as if it were a season finale.

'Clearly every single episode of the six you’ve got left in Season eight is gonna be monumental,' he said.

'Every single episode will be monumental!' Game Of Thrones star John Bradley promises that each instalment of the final eighth season will be 'high-stakes, high-octane'

'I think what we used to call episode nine in Game of Thrones folklore — the episode when everything comes to a head and you get a lot of spectacular sequences — I think you’re gonna get six episode nines this year.'

Speaking to The Huffington Post about returning directors Miguel Sapochnik and David Nutter, he said: '[the final season] needs somebody at the helm who’s done that kind of high-stakes, high-octane direction before for us.'

In September it was announced that Nutter would return to direct at least two episodes of the eighth season while Sapochnik will helm two or three.

Other directors lined up for the job of directing the rest of the season include David Benioff and D. B. Weiss.

Big things: John Bradley, who plays the role of Maester Samwell Tarly, has assured that each episode of season eight will be treated as if it were a season finale

Speaking to The Huffington Post about returning directors Miguel Sapochnik and David Nutter, he said: '[the final season] needs somebody at the helm who’s done that kind of high-stakes, high-octane direction before for us'

Sapochnik is responsible for such episodes as Hardhome and the epic Battle of the Bastards in season six, while Nutter won the Outstanding Directing for a Drama Series 2015 Emmy Award for his work on the Season five finale Mother's Mercy and the Outstanding Directorial Achievement in a Dramatic Series at the 2016 Director's Guild of America Awards for the same episode.

He has also directed others, such as The Rains of Castamere and Dance of Dragons.

Meanwhile, Bradley's character Samwell was last seen talking about the much-discussed parentage of Jon Snow, with Bran Stark in Winterfell.

Back for more: In September it was announced that Nutter would return to direct at least two episodes of the eighth season while Sapochnik will helm two or three

'It would be a waste of $100,000 - it’s not going to happen!' Nikolaj Coster-Waldau blasts 'stupid' HBO boss for suggesting Game Of Thrones shoots multiple finale endings

The final season won't air until 2019, however, leaving fans chomping at the bit to find out how everything will end.

Another actor discussing what's in store during the eighth season this week was Nikolaj Coster-Waldau [who has played Jaime Lannister since season one].

Speaking to Marie Claire, the actor, 47, has criticised HBO's Head Of Programming Casey Bloys by default, for claiming that the plan for season eight was to shoot several versions of the ending, so as to avoid any risks regarding plot leaks.

'You’re not going to waste $100,000 a day to shoot something you’re not going to use. It’s not going to happen,' he insisted. 'Do you think that’s true? It seems really stupid to me.

'Stupid': Nikolaj Coster-Waldau [who has played Jaime Lannister since season one] clearly feels he can say what he likes about plans for the finale

'I mean if it’s true I don’t believe it. I haven’t read the script, so unless they will show several endings that could be a twist, they’re not going to waste that money. They know how expensive it is to shoot.'

Nikolaj - whose character Jaime abandoned his sister [and lover] Cersei [Lena Headey] at the end of season seven - is indeed correct: it's an expensive business shooting the smash hit fantasy series.

Although he appears to have undervalued it, as it was reported by Entertainment Weekly earlier this year that 'throughout the show’s sixth season, a single episode cost around $10m to produce'.

It's thought that Casey Bloys' comments come after the seventh season suffered script and actual episode leaks earlier this year.

Expensive: Nikolaj - whose character Jaime abandoned his sister [and lover] Cersei [Lena Headey, picrtured] at the end of season seven - is indeed correct: the show is costly to producer

According to The Morning Call, he allegedly spoke to college students in Bethlehem, Pennsylvania, and said: 'Because when you're shooting something, people know. So they're going to shoot multiple endings so that there's no real definitive answer until the end.'

In August, script summaries appeared online after HBO suffered from a hack.

An episode also leaked in India, which in fact led to four people being arrested.

Death Is The Enemy - the penultimate episode of the seventh season - was accidentally uploaded to HBO Spain's website.

Locking horns: HBO's Head Of Programming Casey Bloys suggested the multiple endings strategy

Weighing in: The actor has criticised HBO's Head Of Programming Casey Bloys by default, for claiming that the plan for season eight was to shoot several versions of the ending, so as to avoid any risks regarding plot leaks

Death Is The Enemy: The penultimate episode of the seventh season - was accidentally uploaded to HBO Spain's website

Meanwhile, while fans have to wait until 2019 to see how the final charge for the coveted Iron Throne plays out, they're excitedly sharing details of massive new plot hints.

Game Of Thrones fan site Watchers On The Wall has revealed that bosses of the ratings juggernaut have put out a casting call for a whopping eight new characters, a number of whom appear to have small but pivotal roles in the storyline.

Among the characters being added to the fresh influx is an 'authoritative, fit, cool and charismatic' mercenary, likely linked to the menacing Euron Greyjoy (Pilou Asbaek), who went to fetch the Golden Company for Cersei Lannister (Lena Headey).

New characters: Game Of Thrones fan site Watchers On The Wall has revealed that bosses of the show have put out a casting call for a eight new characters for the show's final season

Another telling casting is the search for a 'rough-and-ready' sailor with a 'strong presence' - a strong hint that the spotlight will return to the Ironborn, amid Theon Greyhjoy's (Alfie Allen) efforts to rescue his kidnapped sister Yara (Gemma Whelan).

Many of the new faces coming to the hit fantasy show will be Northern, with casting directors searching for a 'straightforward' farmer, a 'sassy and attractive' girl for a single but memorable scene and a sentry to play opposite the leading cast.

There are also two new guards coming into the fold, with shooting expected to take place in Spain for many of the leading characters from November.

Winter of contentment: Viewership of the show has steadily increased ever since its first season culminating in the Season 7 finale, which became the show's most-watched episode

Tall order: He told students 'when you're shooting something, people know. So they're going to shoot multiple endings so that there's no real definitive answer until the end'

Filming for the TV show has now overtaken the plot in George R. R. Martin's series of fantasy novels, on which Game Of Thrones is based.

Viewership of the show has steadily increased ever since its first season culminating in the Season 7 finale, which became the show's most-watched episode.

One key scene, fans were shocked to see Daenarys Targaryen and Jon Snow - portrayed by Emilia Clarke and Kit Harington - engage in incestuous sex.

Twist: The fantasy epic's tactic of hiding the final reveal amongst multiple false endings is not a new strategy for TV networks

The pair, whose romantic relationship had been built up throughout the penultimate season, finally gave into their passion as they sailed north from Dragonstone as they prepare to face off against the dreaded White Walker threat.

Jon sneaked to her quarters and hopefully chapped the door as they were bobbing along, and his queen was only too quick to invite him inside - and not to talk battlefield tactics.

Fans were treated to a lingering view of hunk Kit Harington's buns of steel as the star, whose father is Sir David Richard Harington, 15th Baronet, portrayed a lovemaking session on the high seas.

In a rather creepy turn, Daenerys' trusted adviser Tyrion Lannister was shown lingering outside in the shadows and waiting outside as they enjoyed their passionate liaison.

No worries: For the cast of the high-rating cable series, it seems like spoilers concerns are the farthest thing from their minds

The fantasy epic's tactic of hiding the final reveal among multiple false endings is not a new strategy for TV networks.

Going all the way back to 1980, Dallas producers shot multiple resolutions to their landmark Who Shot J.R? episode.

More recently, the diversionary tactic has been used for shows like The Sopranos, Breaking Bad and even The Simpsons in order to hide certain plot outcomes and which characters will or won't die.

But for the cast of the high-rating cable series, it seems like spoilers concerns are the farthest thing from their minds.

Chill: Sophie Turner was photographed at Knik Glacier in Alaska, a helicopter in the background as she enjoyed her filming hiatus from the show

Fan favourites Emilia Clarke (who plays dragon queen Daenerys Targaryen) and Sophie Turner (Sansa Stark) have taken to Instagram in recent days to post snaps from their shooting hiatus.

Turner was photographed at Knik Glacier in Alaska, a helicopter in the background. The pic is simply captioned: 'Chillin''.

Meanwhile, Clarke was on set for a promo shoot as the new face of Dolce & Gabbana's fragrance The One.

She made a nod to the show that made her a household name with the caption: 'the very fabulous folks at @dgbeauty decided to take me off a dragon and into their family'.