Could HBO be moving closer to that long-rumored “Game of Thrones” prequel based on George R.R. Martin’s “Dunk and Egg” novellas? That possibility — or at least the hint of one — was just dropped in an interview with HBO programming chief Casey Bloys, by “Entertainment Weekly’s” James Hibberd, who’s probably had more scoops on the world’s biggest show than any other member of the working press.

In the interview, Bloys dodges specifics, but does confirm “preliminary ongoing talks” with Martin. “There are areas we are exploring, but I wouldn’t point to anyone and say, ‘This is what we’re going to do.’ ”

While the words “preliminary” and “ongoing” would appear to be oxymorons when placed side by side, they also may confirm long-standing fan speculation — when “Thrones” ends, HBO has little choice but to find something equally spectacular, or at least something with the potential of “spectacular.”

Great hits have their many blessings, but the single curse is that annoying question fans and the press can’t let go of: What’s next? Movie franchises have it easy, along with the easy solution — just make another “Iron Man!” But TV — as you know — doesn’t work that way. Spinoffs are launched, usually unsuccessfully, or the so-called “IP” (intellectual property) owner waits a dozen years or more, then sells the reboot to Netflix or CBS.

“Game of Thrones” has its own complex set of problems. Set to end with season 8, “Thrones” has already sailed past Martin and his “A Song of Ice and Fire” series — which of course remains unfinished. Martin has mused about ending “GoT” as a motion picture — an idea HBO has resisted simply because that breaks ranks with subscribers.

When asked last spring about an HBO spinoff idea, Martin seemed wide open to the idea, also telling “EW:” “There is certainly no lack of material. Every episode of ‘The Naked City’ — one of the television shows I watched as a kid — ended with a voice-over: ‘There are eight million stories in the naked city. This has been one of them.’ There are eight million stories in Westeros as well . . . and even more in Essos and the lands beyond. A whole world full of stories, waiting to be told . . . if indeed HBO is interested.”

He added, “The most natural follow-up would be an adaptation of my ‘Dunk & Egg’ stories. Each of the novellas could easily be done as a two-hour stand-alone movie for television; that would probably be the ideal way to do them, rather than as an ongoing weekly series. ‘The Hedge Knight’ and its sequels are lighter than ‘A Song of Ice and Fire,’ more in the realm of action/adventure.”

The “Dunk and Egg” stories are set about a hundred years before the key events of “Ice and Fire,” covering the adventures of Sir Duncan the Tall — who would become a member of the Kingsguard — and his squire, “Egg,” who would one day become Aegon V Targaryen of House Targaryen.

That Thursday’s “EW” story on a possible prequel did not mention “Dunk and Egg” may in itself be telling: “GoT” showrunners Dan Weiss and David Benioff have long been cool to the idea of “GoT” prequels. Without specifically mentioning “Dunk and Egg,” Weiss told Variety last spring, “At a certain point, especially if it’s a serialized story, it falls apart and loses its heat and its momentum because there’s a carrying capacity even a world the size of ours has. When you reach that carrying capacity and you try to push it further, people start to wonder when this is going to be over and hope that it will be over soon so they can move onto the next thing. That’s not what we ever wanted.”

Moreover, “Dunk and Egg” is essentially (or superficially) an open road story, charting the travels of two future Westerosian superstars. Sweeping battles, disobedient dragons, and reanimated Lord Commanders of the Night’s Watch are not part of the narrative. Does HBO want something more intimate in scale? Do fans?