Matt Damon is trading one stranded astronaut for another, but he’s here to explain why his role in The Martian is nothing like his surprise cameo in 2014’s Interstellar.

Damon is set to star in Ridley Scott’s The Martian, based on Andy Weir’s 2011 novel of the same name, which tracks the survival of an astronaut left for dead on the Red Planet. But, as luck would have it, he’s not dead, so he has to find a way to survive with extremely limited resources on a planet that is pretty much designed to kill him. Think Cast Away with a mix of space drama, maybe, but Damon wanted to make it clear this film is nothing like Interstellar.

The actor said he originally signed on back when Drew Goddard was attached to direct, before he jumped ship for Sony’s ill-fated Sinister Six spinoff. Damon was reconsidering his own commitment, at least until sci-fi legend Ridley Scott picked up the project. After that, he told Collider he met with Scott about his hesitations on doing The Martian so quickly after Interstellar. Scott’s response, according to Damon? “The movies are totally f**king different. This is gonna be f**king fun. Let’s do this.” That’s all it took for Damon, so he packed up for the Red Planet.

As for what we can expect from the film itself? Damon did a good job of explaining the stakes and setup, noting it’ll consist of his story of lone survival on the planet, interspersed with efforts back on Earth to mount a rescue mission to come and save him. It’s an ambitious pitch, but if they can pull it off, this could be the Interstellar of 2015. By that, we mean the breakout, original sci-fi hit of the year:

“It’s an adaptation of this book, and that’s one of the things that was pointed out by a lot of reviews of the book, that it’s not kind of this existential movie about desolation. You could make that, but I think you probably couldn’t make that at this scale. This character is this incredibly resourceful, optimistic person who just doesn’t bother whinging about things. He just thinks ‘what’s the next problem? Okay, what’s the next problem? I just have to keep knocking down problems in order to stay alive’ because there are so many things…he’s on the very edge of death at all times. If the oxygen tank breaks, he’s gonna die. If the water tank breaks, he’ll die of thirst. If there’s a breach in the half, he’s gonna implode. If all of that works, he’s gonna starve to death. He’s like ‘there are so many things to do’, that his days are full just trying to…and the writer of this book, this guy Andy Weir. I have not talked to him but I read an interview with him. He was talking about how he came up with the concept. He’s like a scientist, he just let the science dictate what would happen if this were me. And he sat there and did it as this kind of thought exercise, ‘well I would need to do this and I would need to do that, and okay well then I would need to do this.’ It’s a very smart person procedurally doing what they need to do to stay alive on Mars. Hopefully people want to see that [laughs].”

The Martian is set to open Oct. 2, after having the release bumped up from its original November date.

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(Via Collider)