SPOKANE, Wash. — “Game of Thrones” author George R.R. Martin acknowledges that HBO could air the final episode of the show based on his books even before the last book in the series comes out — and he’s OK with that.

“Anything is possible,” he told GeekWire during Thursday’s Q&A at the Sasquan science-fiction convention in Spokane. Martin took questions after reading a chapter from “The Winds of Winter,” which will be the sixth book in what’s expected to be at least a seven-volume series.

“Game of Thrones” recently concluded its fifth season on HBO with a blizzard of cliffhangers, including some plot twists that deviate from what’s been laid out in the five books published so far. The sixth season is likely to stray even further from what happens in the yet-to-be-published “Winds of Winter” novel. For example, the character who was featured in today’s reading, Princess Arianne of Dorne, doesn’t even appear in the TV version, Martin noted.

For now, the producers of the HBO series — David Benioff and Dan Weiss — envision doing eight seasons of the show. The saga’s ending is a closely held secret, but Martin has shared it with Benioff and Weiss, and Martin acknowledged there’s a chance HBO will get to that ending by a quicker alternate route.

“The show is moving forward like a locomotive, or sometimes a jet locomotive,” Martin said. “They’re writing 60-page scripts, I’m writing 1,500-page novels. So who the hell knows?

I’m just going to tell my story, and they’re telling their story and adapting my books, and we shall see.

“There was a period where I was worried about that,” he said. “Then I said, to hell with that. Worrying about it isn’t going to change it one way or another. I still sit down at the typewriter, and I have to write the next scene and the next sentence … I’m just going to tell my story, and they’re telling their story and adapting my books, and we shall see.”

So will “The Winds of Winter” be ready by next spring, when Season 6 hits HBO? That’s one question Martin is thoroughly sick of hearing.

“Don’t ask me when the book is going to be done — I’ll ask my minions to lop your head off,” he joked.

George R.R. Martin and award-winning science-fiction author Robert Silverberg will participate in a dialogue at Sasquan, this year’s world science-fiction convention, at 11 a.m. today in Spokane.