John Cusack is not big on genre films, and the only bona fide thriller on his resume is 2003’s “Identity.” But when Cusack was sent the script for “1408,” about a debunker of the supernatural who checks into a hotel suite where, according to myth, no one checks out alive, Cusack had to rethink his natural bias for two reasons.

First, it was based on a Stephen King short story, and second, it offered the ultimate actor’s challenge: Could he hold a screen on his own in a confined space for 94 minutes?

Q. Are you a Stephen King fan?

A. Oh, yeah, he’s an underrated writer. People get hung up on the horror-science fiction thing, but when you read his best stuff, it’s all character. That’s why so many good filmmakers and actors have been drawn to his stuff. Think about it. Jack Nicholson, Sissy Spacek, Kathy Bates, Anthony Hopkins, Johnny Depp, Tom Hanks, Ed Harris – those are all pretty particular people.

Q. Do you have a favorite King film?

A. Well, I know that King doesn’t like it, but Stanley Kubrick’s adaptation of “The Shining” is incredible. I first saw it when I was, like, 12, and I was afraid to walk home by myself. “Carrie” is pretty great; that really holds up after, what, 30 years? “Stand by Me,” not a horror film, just a great movie about growing up. There are a lot of clunkers, too, but that’s what happens when you’re as prolific a writer as he is.

Q. Aside from some pretty tense scenes with Samuel L. Jackson (who plays the hotel manager), “1408” is pretty much all Cusack, all the time. Was that the challenge for you artistically, or was it just about giving the old ego a blowout on the highway?

A. It was more like a maniacal dare to myself. No safety net, no tightrope even. And without giving too much away, a lot of what’s going on in the room really isn’t, you know, because it’s CGI stuff that’s added later. You really do have to work yourself up to it because it’s a psychological hell this guy is going through, and since it’s a thriller, that has to increase in intensity for every scene. It’s not like a one-man show where you stroll around the stage telling old stories. It’s stripping down, showing what’s inside. So you know you could fail miserably, and yet you still feel driven to try.

Q. Since it’s primarily just you, the director (Mikael Hafstrom) and the script, were you more personally involved than you might be on a film with a larger cast?

A. Normally I’d be humble and say I was just trying to help get the filmmaker’s vision on screen, but this was, by its nature, real collaboration: More like professional wrestling, really, trying to pin this thing down every day while ramping up the drama. I mean, if we do our jobs right, we have to scare you and make you think about why you’ve been so unhinged about this. So, yeah, I got involved a lot more than usual. Plus, you know, I am a writer, so I have some ideas.

Q. Yeah, I see that you wrote one of the 20 or so movies you have coming up. Are you building a new house or something?

A. Since I do most of the movies I like to do for something like free, I just have to earn enough to pay the rent. The movie I wrote was with Mark Leyner, who’s a great satirist – he used to do a lot of stuff for the New Yorker – and Jeremy Pikser, who wrote “Reds” and “Bulworth” with Warren Beatty. It is about an assassin who’s looking to take out a Middle East oil minister, but a lot of complications get in the way. It’s being called “War, Inc.” while it’s being sold to foreign markets. But it will probably have another title before it comes out next year. It’s wild. The cast includes my sister [Joan], Ben Kingsley and Hilary Duff, so that tells you something right there.