From Spielberg's surprise appearance to the screening's technical glitch to a standing ovation, here's what went down at the world premiere of the sci-fi film.

Ever since SXSW announced two days ago that Steven Spielberg’s Ready Player One would be its secret screening on Sunday night, it’s been the hottest ticket at the Austin-based festival.

So it's no surprise that the town was buzzing with excitement last night when hundreds of festivalgoers — a mix of press, badge-holders and fanboys — were treated to the first-ever viewing of the Warner Bros. movie, based on the popular sci-fi book by Ernest Cline. The line to get into the showing wrapped around an entire block, and many people had been waiting for hours in hopes of securing a spot inside the Paramount Theater.

But the biggest shocker of the night was when SXSW’s director of film Janet Pierson announced that Spielberg himself (who wasn't included in any promotional materials leading up to the event) was there. After walking onstage to rapturous applause at 9:30 p.m., he told the crowd, “This is not a film that we made — this is, I promise you, a movie.” He emphasized that Ready Player One is a movie that should be seen on a big screen. “I’m wondering if this screen is a big enough screen,” he joked, “because we made this with a lot of ambition to fill the screen, and we hope we can do that tonight.”

Spielberg went on to explain that he wanted to make ready Ready Player One not only because he loved the book but also because he’s a self-proclaimed gamer. “I’ve been a gamer ever since 1974 when I played the first pong game on Martha’s Vineyard while filming Jaws,” he said, the energy in the crowd pulsing. But he also set out to make the film for people who don’t play video games and who may have never played one in their life. “This isn’t a film that you must have gotten into the gaming world to really get and get involved with. This is not just for gamers,” he insisted.

The director also teased that the movie has a lot of cultural references. “Just remember one thing: the side windows are for cultural references, the windshield is for the story. If you look straight ahead, you can always follow the story; if you look out the side windows, you may miss the story,” he noted. In addition to writers Cline and Zak Penn, castmembers at the premiere included Tye Sheridan, Olivia Cooke, Ben Mendelsohn, Lena Waithe, Win Morisaki and Philip Zhao. Also spotted in the crowd: Warner Bros. CEO Kevin Tsujihara, president and chief content officer Toby Emmerich and president of worldwide marketing Blair Rich. Absent was Mark Rylance, Simon Pegg and T.J. Miller, the latter of whom was the only actor to not have his face ever show in the film, sparking speculation that scenes of his may have been cut.

The screening hit a bit of a roadblock when nearly two hours in, the speakers blew out during a particularly climatic loud explosion sequence and the movie lost sound entirely. Event organizers began scrambling to fix the malfunction but when they tried to simply replay the scene, the same thing happened. Pierson grabbed a mic and told everyone her team was working to get the film back up and running, and that in the meantime, it’d be a good time to take a bathroom break. When the technicians restarted the film again, this time turning the sound down during the loud sequence, it played with no issues. In response, the crowd cheered and applauded, signaling that the brief, five-minute glitch only served to pump up the audience more.

When the film finished, the cast, Spielberg and Cline jumped back onstage for a short Q&A, receiving a standing ovation from the audience in the process. “This is perhaps the greatest anxiety attack I’ve ever had,” Spielberg said, alluding to the hiccup during the screening, to laughs from the crowd. He went on to describe how making Ready Player One was different from other films he’s helmed. “When I make a movie that I direct behind the camera… I’m pretty much in control of that. But when I decide to make the movie sitting in the audience with you, sitting in the seat right next to you, that means I’m making the picture for you,” he said, “and your reaction is everything.”

“It’s been the best two hours of my whole life,” said Sheridan, who is from Austin and brought his whole family with him to the premiere. “Except for the part where the movie stopped and the sound wasn’t working, that kind of sucked — but it built it up, did it not?” The crowd cheered again. Earlier on the red carpet, Sheridan told The Hollywood Reporter that he got "super, super excited" when he heard that Spielberg was working on a script about virtual reality because the actor has been an avid VR fan for a while. "I thought it was going to be a huge milestone and make history, and now we're here," he said.

The Ready Player One team spent the rest of their time on stage fielding questions from audience members. When Spielberg was asked what made him want to turn the book into a movie, the director explained that he actually read the screenplay before he read the novel. The scene that made him want to do it was a four-page dialogue scene between the main characters Parzival and Art3mis, the most they talk together. “And I said, ‘If I can capture that in a bottle, if I can get that relationship, then that is a movie worth making. Because this is a character movie as well as a big action movie,’ he said.

After the Q&A wrapped a little after midnight, guests headed straight to the afterparty, held at the building that served as the home for the Ready Player One VR experience over the weekend. The line to get in was halted around 12:45 a.m. because the party had hit capacity, so attendees had to wait for other guests to leave before they could enter. Inside, the crowd enjoyed a live performance by Joan Jett and the Blackhearts, sit in a DeLorean and play a virtual reality game similar to those in the movie.

As for whether we'll see more Ready Player One on the big screen, it seems the ball is in Cline's court. The author is currently writing the sequel to the book, which he says will go in a different direction that the movie. Cooke told THR that she's signed on for more films, should the studio make them. "There's definitely been discussion. It's something we've all been talking about for a while because it's a universe and a whole world to play in," acknowledged Penn ahead of the screening, cautioning, "But the movie has to come out first."