Huge news for Stephen King‘s upcoming limited series version of The Stand.

CBS All Access revealed Thursday that four key roles have been cast, plus King is writing new material for the finale of the 10-episode series that will go beyond the story in his apocalyptic 1978 novel.

First the casting, some of which confirms previous reports of actors who were in talks for the roles:

James Marsden (Westworld) will portray Stu Redman, “an ordinary working-class factory man in an extraordinary situation with a damaged quality to him that belies his exterior.”

Amber Heard (Aquaman) will play Nadine Cross, “a deeply conflicted woman who feels the consequences of her actions, but is still compelled by her allegiance to Randall Flagg, the Dark Man.”

Odessa Young (A Million Little Pieces) will play Frannie Goldsmith, “a pregnant young woman navigating a strange new world, who also has the foresight to recognize that there is evil lurking beyond the Dark Man.”

Henry Zaga (13 Reasons Why) will portray Nick Andros, “a young deaf and mute man who finds himself in a position of authority when the unthinkable happens. He has a habit of risking his own well-being for the safety of others.”

But perhaps the biggest news for King-philes is that the author himself will pen the show’s finale, and it will include “a new coda that won’t be found in the book” that will reveal more about what happened to the survivors. (Presumably, they mean books, as The Stand was originally released in one form and then was re-released an expanded version with 500 additional pages).

The Stand tells the story of a plague that wipes out 99 percent of the population with the survivors embroiled in an elemental struggle between good and evil. The novel was previously adapted into a well-regarded ABC miniseries in 1994. There’s no premiere date for the new series yet.