Where does the story pick up this season on HBO’s fantasy epic “House of the Dragon”?

“So,” the actor Tom Glynn-Carney told a reporter on Monday night at the Season 2 premiere at Manhattan’s Hammerstein Ballroom, everything “hits the fan.”

His character in the “Game of Thrones” prequel, the newly crowned King Aegon II Targaryen, holds a grip on the throne that is tenuous at best. His brother has just killed their nephew in what could best be described as death by dragon chomp. And his sister Queen Rhaenyra Targaryen is on the brink of going nuclear — as Targaryens tend to do — likely with more dragon chomping.

Even as Mr. Glynn-Carney, Matt Smith and other “Dragon” actors laid out the violence in store for the new season — which returns June 16 — the show’s impending civil war stood in stark contrast to the evening’s cocktails and joviality, with not a single silvery wig in sight.

Some actors have struggled to recognize each other without them, said Phia Saban, whose character, Queen Helaena Targaryen, plays a critical role in an early episode. (There were 114 wigs used this season, HBO’s chief executive Casey Bloys said at the premiere, and — back to the dragon chomping — 33 gallons of fake blood.)

The night was also a victory lap for a risky spinoff that had early hopes of living up to its pop culture juggernaut of a predecessor. “Dragon” averaged, according to HBO, around 29 million viewers each episode in its first season — numbers that aren’t far from the records broken by “Thrones.”

“The biggest thing that we had coming into Season 2 was just knowing that we had our audience and that they trusted us,” the showrunner and co-creator Ryan Condal said in an interview on the green carpet, “and that we just had to now pay off on what they were expecting.”

Some of the actors dressed according to the season’s color-coded rivalry, which has been played up in the show’s marketing. Team Black for the Targaryens aligned with Rhaenyra — played by Emma D’Arcy, who wore a rhinestone-covered black Celine jacket — and Team Green for the Hightowers and Targaryens supporting Aegon’s claim. (Mr. Glynn-Carney’s velvet suit was a deep pine.)

Olivia Cooke, whose character, Queen Alicent Hightower, often wears her house’s emerald hues, opted instead for a cerulean Loewe gown: “I’m bored of green now,” she said.

Ms. Saban paid homage another way, with a buoyant robin’s egg bubble of a Stella McCartney dress. “I kind of feel like a dragon egg,” she said on the carpet, giving a little twirl.

At the after-party, in the shadow of a massive Thronesian tree with blood-red leaves, cast members mingled with more than 450 guests, a mix of staff and executives from HBO and Warner Bros. Discovery alongside a smattering of actors and influencers.

Ms. Cooke spoke in one corner of the ballroom with the actor Justin Theroux. He was there to support his friend Clare Kilner, a director on the show. The actress Emilia Jones, from “CODA,” slipped in late sporting a new mullet. (The timing and her hair, she said, could be attributed to a new HBO crime drama series she is filming alongside Fabien Frankel, another “Dragon” actor who plays Ser Criston Cole.)

Swerve Strickland, a professional wrestler, carried a blindingly embellished All Elite Wrestling championship belt over his shoulder throughout the night. Some of his own performance in competition, he said, has been inspired by the show: “I kind of pull a lot of things,” he said, adding, “a lot of the story and character development are what I do in the ring, too.”

“I was a bad guy for a while,” he added, noting that his character feels similar to Mr. Smith’s morally gray Daemon Targaryen. “Now I’m kind of switching over, but I still have bad-guy elements.”

A long line of attendees gathered beside a replica of the Iron Throne itself, waiting to take a photo surrounded by heaps of swords.

Nearby, a table stacked with slices of pizza played up the impending onscreen battles with a more familiar New York rivalry: Would guests select Roberta’s Pizza and its Calabrian chile “Slice of the Seven Kingdoms”? Or John’s of Bleecker Street’s cherry pepper and ricotta offerings?

(There were 60 large pizzas on hand, those working the ovens said — John True, a manager at Roberta’s and a massive “Thrones” fan, added that he had eagerly volunteered to work the party on his day off.)

The evening’s specialty cocktails added to the fiery theme, including a tequila-based concoction with jalapeños and, of course, a dragon fruit lemonade.

There was no sign, however, of any Negroni Sbagliatos.