WARNING: Potential "Game of Thrones" spoilers ahead.

In a series known for killing off main characters, fans may be relieved to know some "Game of Thrones" heroes and heroines are safe. Or at least, they were in author George R.R. Martin's original plan for the series.

Martin submitted a general outline for the then-planned trilogy, "A Song of Ice and Fire." The series eventually grew to a now-planned set of seven books, and has changed a lot from his starting plot points.

But we're hoping one section of the general plan has remained a part of Martin's overall story. After telling the editorial reviewer that the cast of characters would be ever-changing — with lots of unexpected deaths — Martin makes it clear that five key protagonists will survive.

"Five central characters will make it through all three volumes, however, growing from children to adults and changing the world and themselves in the process," Martin wrote. "In a sense, my trilogy is almost a generational saga, telling the life stories of these five characters, three men and two women."

Just who are these five key players? Fans can breathe easy that they are bona fide fan favorites: "The five key players are Tyrion Lannister, Daenerys Targaryen, and three of the children of Winterfell, Arya, Bran, and the bastard Jon Snow," Martin wrote.

So — if fans are to be optimistic and take Martin's original word at face value — Tyrion, Daenerys, Arya, Bran, and Jon could survive the entire series.

Jon technically died, but was brought back to life in the television adaptation, something fans can expect to see in the coming books if the fan theories are correct. Killing him off for a second time would be unlikely, even with Martin's fondness of subverting expectations.

Martin's sixth installment of "A Song of Ice and Fire" is still in the works, with no publish date announced. In the meantime, HBO's television adaptation has overtaken his written material. Showrunners David Benioff and D.B. Weiss were told some key plot points by Martin, and they know his planned ending as well. But for a majority of the onscreen action seen in "Game of Thrones," fans have no way of telling whether or not that storyline will happen in the books. The characters who survive in the show likely won't be the same set of people who make it through the written series.

Readers will have to wait until the final two books of "A Song of Ice and Fire" are published to know the fates of their favorite characters, but for now, we're banking on these main five surviving it all.

This article has been updated from its original version.