On July 12, HBO held an exclusive Los Angeles premiere for "Game of Thrones" season seven. From a star-studded "blue" carpet to the screening of the first episode (followed by an epic after-party), INSIDER was on hand to witness all the magic.

The cast arrived to the Walt Disney Concert Hall in downtown Los Angeles and hit the blue carpet — aptly colored to match the wintery theme of season seven.

Most of the cast was there, including former members. Kit Harington (Jon Snow) and his girlfriend Rose Leslie (who played his on-screen love Ygritte) looked dapper.

Kit and Rose met on the set of "Game of Thrones" season two. Neilson Barnard/Getty

HBO unlocked a new Snapchat lens recently, and the "Game of Thrones" stars were testing it out on the blue carpet. Here's Sophie Turner (Sansa Stark) doing her best White Walker impression:

Turner spoke with INSIDER about Sansa's evolution and the pending struggle she'll face with being the Lady of Winterfell. "It's kind of her struggle with newfound power," Turner said. "That's the theme for her — power."

After the stars made their way through blue carpet, it was time for the screening of season seven's first episode.

The episode screening

Inside the theater, an orchestra and chorus were set up and waiting.

"It's Always Sunny in Philadelphia" co-creator and star Rob McElhenney was super excited at the prospect of watching a whole episode scored with a live orchestra.

But the orchestra wasn't there to play along live with the new episode. Instead, composer Ramin Djawadi came out and led the musicians through a mini version of the "Game of Thrones" Live Concert Experience — a musical spectacle that toured for nine months after season six.

The audience watched as a recap montage of season six was shown, complete with a condensed version of "The Light of the Seven" and Cersei's wildfire plot. Then the orchestra left the stage.

The lights dimmed, and Jon Snow (Kit Harington) spoke over the loudspeakers.

"Night gathers, and now my watch begins. I shall take no photos, and hold no phones, and spread no rumors on social media," Harington said. "I am the shield that guards the realm from spoilers."

The bit continued, emphasizing the extreme secrecy required by HBO about the episode we were about to see, which means we won't tell you anything here about the episode (other than it was really fantastic and garnered lots of applause, laughs, and awe-struck silence from the audience).

The epic after-party

After the premiere, the cast and guests made their way across the street to a low rooftop, where the view was LA's skyline and the Walt Disney Concert Hall, decorated with elaborate projections.

The dance floor was a huge map of Westeros. Neilson Barnard/Getty

The projections were very impressive, sometimes showing Drogon flying and breathing fire:

At other times the Night King's face was staring down at the party guests, or it was a montage of every cast member's official season seven character poster.

A DJ clad in all-white was blasting jams from right in front of an iron throne replica.

Though the event space was large, there were stars covering every square inch. Jimmy Kimmel, Queen Latifah, and several cast members from HBO's "Silicon Valley" (Martin Starr and Jimmy O. Yang) and "Girls" (Alex Karpovsky) were in attendance.

Queen Latifah must be a big "Game of Thrones" fan. Neilson Barnard/Getty

Most of the cast had turned out for the premiere, from Nikolaj Coster-Waldau (Jaime Lannister) and Gwendoline Christie (Brienne of Tarth) to Alfie Allen (Theon Greyjoy) and Gemma Whelan (Yara Greyjoy).

Allie Teilz (a DJ and girlfriend to Alfie Allen) poses with the "Game of Thrones" stars. Neilson Barnard/Getty

Sophie Turner brought boyfriend Joe Jonas and his brother Nick Jonas to the after party. Sophie and Joe looked happy and cozy sitting together, while Nick went to the photobooth and fancied himself King in the North.

A post shared by Nick Jonas (@nickjonas) Jul 12, 2017 at 11:11pm PDT

Isaac Hempstead Wright (Bran Stark) looked dapper in a suit next to the stunning Nathalie Emmanuel (Missandei).

Nathalie Emmanuel is pulling double duty in franchises. She also stars as Ramsey in the "Fast and Furious" movies. Neilson Barnard/Getty

Jerome Flynn (Bronn) and Iain Glen (Jorah) were hanging out with Conleth Hill (Varys), while Liam Cunningham (Ser Davos) and Richard Dormer (Beric Dondarrion) posed together for a photo:

Ser Davos and Beric have never met on the show, but the two actors seem chummy. Neilson Barnard/Getty

The most notable absences among the cast were Emilia Clarke (Daenerys Targaryen), Lena Headey (Cersei Lannister), and Peter Dinklage (Tyrion Lannister). But at the end of the night, when everything was winding down (and the badass silver skull centerpieces had all been sneaked away in purses), the Night King was left watching over Los Angeles.