As the world's most successful television program prepares to kick off its penultimate season, its stars descended on Hollywood for the gala premiere at the Walt Disney Concert Hall in Los Angeles.

It's not your typical venue for a television program premiere, but then your typical television program does not get a full orchestra concert performance conducted by the show's composer Ramon Djwadi.

British-born actress Sophie Turner, who plays Sansa Stark in the fantasy series, said the cast were bittersweet at the prospect of following this season with a final season that would bring the story – for now – to a close.

"I feel very emotional about it, it's my family, my friends, my loves, I will be losing a huge part of my life," she told Fairfax Media.

The penultimate season of the show will be its seventh so far; an eighth and final season is planned for either 2018 or 2019. In part due to the immense popularity of the series, there are already talks of spin-offs and prequels.

"It feels like a death in the family," she added; a perhaps unsurprising comparison for a show which has displayed an almost disturbing appetite for killing off characters.

"It's also exciting, and liberating," Turner said of the show's inevitable conclusion. "It feels like a graduation, which is always bittersweet."

While the series is one of America's biggest television exports, it is curiously un-American: it is filmed in Belfast, in Northern Ireland, and on location in places such as Croatia, Spain, Morocco and Malta.

It also features a mostly international cast.

The series is based on A Song of Ice and Fire, a series of fantasy novels written by George R. R. Martin; the first book in the series was titled A Game of Thrones, from which the television series took its title.

The books are set in a fictional land, Westeros, where seven kingdoms jockey for dominance, beset by internal discord, clashes of royal dynasties and the threat of an impending winter.

Liam Cunningham, who plays Davos Seaworth, said the immense scale of the show's marketing and fan mania was almost unprecedented.

"There is this level of weirdness, I have had women faint in front of me and I am not even in One Direction," Cunningham told Fairfax Media.

"But to be fair, it's not on the back of something that was big because it was big," he says.

"This is a beautiful show. It doesn't patronise, it doesn't treat its audience as numbers, the last thing that anyone wants on this show is to let them down."

Cunningham said the series was almost a high-class soap. So, are we talking EastEnderos?

"Is that the headline?" Cunningham asks, laughing.

"But isn't the best drama like that?" he adds. "Shakespeare wrote like that and there is a Shakespearean aspect to this. It's high drama but it's also about the small things in people's lives."

Cunningham said one of the most compelling themes in the show's penultimate season would be the emergence of female power in Westeros.

"We have this almost medieval, male-driven society, and where we find it now, the women have all the power," he says. "It's flipped on its head, I find it incredibly interesting and that's where we kick off."

Turner agreed, noting that the key female political players in Westeros were now "just as powerful if not more powerful as some of the men in the show. I am proud to be part of a show that does that."

Cunningham added that the final season would more cinematic, "because we spent the same amount of time filming seven episodes that we would usually spend doing 10. It's going to be stunning to look at."

The guest list for the premiere included the show's stars Gwendolyn Christie (Brienne of Tarth), Kit Harington (Jon Snow) and Maisie Williams (Aria Stark), as well as its producers and co-creators David Benioff and Dan Weiss.