House of the Dragon is proving to be a hit right out of the gate. The Game of Thrones prequel set 200 years before the events in that show reported record high numbers for an HBO series premiere.

The series, which premiered Sunday, tells the story of House Targaryen, the dragon-riding family that conquered Westeros and established the Iron Throne. The prequel's predecessor, Game of Thrones, was famous for its high ratings, with every season drawing in more viewers than the last. Expectations for House of the Dragon were therefore high, and it seems to have delivered. Per Variety, Warner Bros. Discovery reports that 9.99 million viewers tuned into the inaugural episode of the series.

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Following reports of HBO Max crashing after the series premiere, it was a certainty that the show was going to be a ratings success, but this figure places the show as HBO's most-watched series premiere of all time. For comparison, Game of Thrones premiered to 4.2 million viewers in 2011 and 17.9 million viewers for the premiere of its eighth and final season. Euphoria, HBO's second most-watched show of all time, premiered to 2.4 million viewers, a figure 76% less than that of House of the Dragon.

House of the Dragon House Targaryen at the Great Council HBO

In a time when HBO Max has been cutting content left and right, this news bodes well for House of the Dragon's future. The show has already featured a departure from Game of Thrones' production by more closely involving franchise creator George R. R. Martin. Martin, who has previously stated he does not want to end up like Stan Lee in terms of creative control, is a much more active participant behind-the-scenes of House of the Dragon.

Though the series is boasting high numbers, the endurance of its viewership remains to be seen. While episode 1 of the show had a promising beginning, many viewers still harbor negative emotions towards the finale of Game of Thrones. Though they may have been curious to check out the prequel, they’ll have to remain interested in order to ensure that the show has legs on which to stand.

With HBO trying to turn Game of Thrones into a lead franchise of theirs, the show will have to continue to do well in order to sell executives on the feasibility of future projects. Currently, it’s known that a Jon Snow-centered sequel is in the works, as is an adaptation of Tales of Dunk and Egg, which tells the story of Daenerys Targaryen's great-grandfather and his apprenticeship to a minor knight of the Seven Kingdoms. Ultimately, the fate of these spin-offs lay in the hands of House of the Dragon.

House of the Dragon airs Sundays at 9 PM EST on HBO.

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Source: Variety