George RR Martin doesn’t know how HBO's 'Game Of Thrones' ends

George RR Martin might know how A Song Of Ice And Fire ends, he’s had that planned since before he wrote the first sentence. But he has no idea how HBO’s adaptation, Game Of Thrones, will conclude.

That’s partly because he hasn’t read the season eight scripts, or even visited the sets. And, as he told EW, he has a very good reason.

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“I haven’t read the [final-season] scripts and haven’t been able to visit the set because I’ve been working on [the next book, The] Winds [Of Winter],” Martin told EW.

So, because the show deviates from the books in many key ways, George doesn’t know how the show will play out in the final season.

“I know some of the things. But there’s a lot of minor-character [arcs] they’ll be coming up with on their own. And, of course, they passed me several years ago. There may be important discrepancies.”

Still, he’s grateful for the show. “It’s been an incredible ride. And almost all of it has been great. Obviously, I wished I finished these books sooner so the show hadn’t gotten ahead of me. I never anticipated that.”

Read more: HBO boss isn’t sold on ‘GoT’ prequel plans

But if Martin’s worried that the show’s going to spoil those books he hasn’t quite got to yet, showrunner David Benioff told EW that fans won’t be able to tell what’s from the books and what’s from the show, which will preserve some of the mystery for fans.

“[The concern] used to be that the books would spoil the show for people — and luckily it did not for the most part. Now that the show is ahead of the books, it seems the show could ruin the books for people. So one thing we’ve talked to George about is that we’re not going to tell people what the differences are, so when those books come out people can experience them fresh.”

Game Of Thrones returns to Sky Atlantic on 15 April.