AMC's "The Terror" is an amazing limited series starring some familiar faces from "Game of Thrones" and "Mad Men."

The historical-fiction series is a sci-fi horror twist on the stories of real people who went on an expedition to the Arctic and never returned.

Business Insider spoke to creator and showrunner David Kajganich, who has been attached to the project since before the novel it's based on came out in 2007.

Before David Kajganich came to Los Angeles to start screenwriting, he worked as a wilderness instructor and guide.

Years later, that led him to his first job running a TV show: AMC's brilliant and haunting limited series, "The Terror," which aired its finale Monday night. The series, which premiered on March 26, is based on the 2007 Dan Simmons novel of the same name. Both are fictionalized accounts of Sir John Franklin's lost expedition to the Northwest Passage. It stars Jared Harris as Crozier, Tobias Menzies as Fitzjames, Ciarán Hinds as Franklin, and Paul Ready as Goodsir.

Kajganich told Business Insider he had "a long history" with "The Terror," a project he'd been attached to since 2007. He recalled telling the story of the lost Franklin expedition in his years as a guide. When he started his career in Hollywood, he heard Dan Simmons was writing a novel about the story called "The Terror." Simmons was adding a Victorian gothic horror element to the story. Kajganich got a copy of the book before it was published, and tried to get the rights to adapt it into a movie. He eventually got himself hired as the screenwriter, but it was too late. Universal had another planned project that was too similar: Guillermo del Toro was set to direct an adaptation of an H.P. Lovecraft story called "At the Mountains of Madness," which is also about a disastrous and horrific expedition set in the Arctic.

Kajganich said the rights to "The Terror" went to HBO, and "for a little while" David Fincher was attached. Over time, the idea shifted from a two-hour movie to a television series, and it was pitched to AMC. AMC declined.

"They said they weren't comfortable with an anthology series at the time," Kajganich said. "'American Horror Story' was just starting its second season, so they could've been ahead of that curve, but they just weren't ready to take the plunge."

The project was with Netflix for a time, but one day, AMC called "almost out of the blue" and said they figured out a model where they could do "The Terror" as a limited series.

"A lot of people understood that it was a great project," Kajganich said. "They just knew it was going to be an expensive proposition. It's a lot of white guys dressed in winter clothing."

While Kajganich had been in a writers room and has written screenplays across a variety of genres (he wrote the screenplay for "Suspiria," the next film from "Call Me by Your Name" director Luca Guadagnino), he hadn't run a writers room before. So he needed help running the show, and chose Soo Hugh, whose credits include "The Killing" and "Under the Dome."

Business Insider spoke with Kajganich in early May, and discussed the long development of the project, the benefits of a television series versus a movie, and the decision to completely change Lady Silence, one of the few female characters, from how she's depicted in the book.

This interview has been edited for clarity and length. Warning: Minor spoilers if you haven't watched "The Terror."

Carrie Wittmer: What were some of the challenges of extending a story that for years you had broken down into a two-hour movie?

David Kajganich: I haven't taken that outline out and reread it, because I'm a ... little bit afraid to confront the fact that I would've been willing to subtract so much of what's great about this book. Ten hours ended up being perfect. We were able to cover all the character arcs we wanted to cover.

Wittmer: You did such a great job establishing all of these characters very quickly. It's devastating that all these people are dead. I mean ... most of them are dead. And I knew that they would be dead, but it still hurt.

Kajganich: Can you imagine when you first started watching? We really kill off a lot.

Wittmer: Ciarán Hinds went a lot sooner than I anticipated, which was a "wow" moment. I really liked Goodsir. I cared about him very quickly, so much. And even Fitzjames, too. And this cast was just incredible. How involved were you in the casting?

Kajganich: We knew casting was going to be a major success or failure of this show. We have so many characters, and characters who increase in value as the season goes on. We knew we were going to be pulling this fast one with making you think Ciarán [Hinds] was the main character but it's really Jared Harris. We also knew it was going to be exclusively white men and that they were going to be in winter clothing. So we had to cast people who felt different from one another, or differences you could notice under these crazy costumes and darkness and blinding snow. They really had to feel different. Even if you never knew their name, you would know when someone walked in a scene, "Oh, that's that guy."

Wittmer: You definitely pulled that off. I didn't think about this while watching the show, but you're right — when one of the white guys walks into a room, you know who that white guy is.

Ciarán Hinds and Jared Harris in an early episode of 'The Terror.' AMC

Kajganich: We read a lot of people for this show. And we had a lot people come in because there are a lot of parts. We told Kate [casting director Kate Rose James] and she was really happy to operate under this mandate of not casting people because of what they had done, because of something in their previous credits. We wanted to match actors with roles they had never played before because we thought that would be one of the best ways to get all of these actors' A-games ... give them roles that were different.

Wittmer: There's these men throughout the course of the show who start to show their true colors as their circumstances change. Some are worse than others, and there's certainly this prominent theme of the male ego and toxic masculinity. It's very relevant.

Kajganich: We talked in the writers room about what we wanted to bring to Lady Silence's character. Our version of her is probably the biggest departure from the book. In the novel, she never has a tongue, so she never speaks. She functions in the book as a kind of, possibly mystical, possibly frightening "other." We wanted to turn her character into a full protagonist on her own terms, and not have her story subservient to any of the male characters. And what comes with that is the unpacking of this toxic masculinity you're talking about. It's one of the ways we assured AMC that this wasn't going to devolve into just a guy show. In the same way we did research about sailing in the 1840s or Inuit culture in the 1840s, we did a fair bit into manhood — the male identity in the Victorian Era. We tried to unpack that in an interesting way for the audience, mostly by using this slow-motion disaster as a chance to show how men with these different sets tools respond to fear. How do different men with different sets of tools respond to alienation and isolation, and all those kinds of anxieties? Hopefully we did an interesting enough job that it doesn't feel like we judged our characters, but it feels like we exposed them.

Nive Nielsen as Lady Silence. AMC

Wittmer: Is the ending similar to what happens in the books?

Kajganich: No. It's quite different. At the end of the novel, Lady Silence and Crozier marry and have children. We very strictly didn't want her arc to be that she's the wife or the girlfriend, or the lover of any of our characters. We didn't want to simply use a female character as a sexual character or a romantic interest. We wanted to see if we could pull off a season of television where a female character didn't have to engage on any of those levels: she was engaging with the story in a way that she's Crozier's equal as the season goes on. They are both captains who weren't ready to be captains when they were promoted through this disaster, and they both lost their ships, and they both have to pay the price of that at the end of the show. If one wanted a final coda to a season of TV that was about unpacking the consequences of toxic masculinity, I think it's a pretty provocative way to end the show, and it's definitely not how the book ends.

Wittmer: I can't imagine the show with Lady Silence as a romantic interest. That would've been strange.

Kajganich: It would've been. We were just delighted to be able to have a character like her on the show, functioning with her own story on her own terms. It was really a joy to plot.

Although a majority of the series is set outside, it is almost entirely visual effects. AMC

Wittmer: And the actress [Nive Nielsen] is amazing.

Kajganich: Ah, she is amazing. From the beginning — and we prayed that we would have enough time and we did, thank goodness — we knew that we didn't want to cast European or Asian actors in these Inuit roles. We really wanted to find Inuit actors for them. The difficulty in that is finding a way into these Inuit communities, many of which don't have internet, or if they do it's pretty limited access. So we hired casting consultants who are part of the Inuit community and have worked with the Inuit community to help us get the word out. Nive had acted once before in a small role in a Terrence Malick film [2005's "The New World"] and she's the front woman of a band [The Deer Children]. So she felt really comfortable in front of the cameras on set with the crew surrounding her. She's so grounded that she wasn't thrown by walking into a community where she was one of the only female actresses. We had plenty of women on the crew and that was helpful, but the very first scene she shot is a scene from episode two where she has to argue with Jared Harris, Tobias Menzies, Ciarán Hinds, and Paul Ready.

Wittmer: Wow.

Kajganich: In retrospect, it was a crazy thing to ask her to do first. But she wanted to! She wanted to just break through the ice and start working. And boy did she nail that scene — and every scene she's in. She's fantastic.