The Dark Tower: Matthew McConaughey awaits the end of the world as The Man in Black 

'The Dark Tower': Idris Elba fires up Stephen King's Gunslinger

The big changes 'The Dark Tower' will make to Stephen King's books

This Week's Cover: Gatecrashing Stephen King's 'The Dark Tower'

Sometimes two different paths can lead you to the same place.

That’s what happened to Matthew McConaughey as he considered two potential roles, both of them monsters from the mind of Stephen King – Walter, The Man in Black from

 or Randall Flagg from a planned adaptation of

As readers know, they are actually one and the same – separated, in our world, only by film rights. With

backburnered for now, McConaughey chose the path that takes this mythic Walkin’ Dude through the realm of Mid-World, a parallel universe where he has already helped engineer Armageddon.

In director and co-writer Nikolaj Arcel’s film (out Feb. 17), Walter is on the run, hot-footing it away from Idris Elba’s warrior-knight, The Gunslinger, who has a vendetta to settle against the sharp-dressed, smiling warlock.

The Man in Black plans to bury his pursuer in the wreckage of even more worlds by destroying the Tower that stands as the hub at the center of many dimensions. (He

, in the mythology of King’s books, is just one such realm.)

marks one of the Oscar-winner’s few outright villains, but… of course McConaughey doesn’t see him that way. Bad guys never do.

“Well, he is a man, actually,” McConaughey says during a break between scenes, sitting on a ruined couch on the rooftop of an abandoned shopping center in Cape Town, South Africa. “They wanted to go very human and grounded with this. Obviously there are mythical proportions of good and evil in Walter. But we didn’t want to go overly fantastic. That would drop the humanity. So Walter, for me, is a man who exposes hypocrisies.”

But if we’re going to talk about total honesty… Walter’s a bad, bad man.

McConaughey grins. The wind plays in his spiky, crow-feathered hair. “You know, he’s not literally the Devil, but I sure as hell think about him like the Devil. I think like the Devil would.”

The Devil tempts. The Devil gets you to say yes when everything else inside you is screaming no. The Devil is good at making the world okay with everything about it that’s broken or wrong.

“There’s a great Black Sabbath line that fits the guy very well,” McConaughey says. “

Follow me now / and you will not regret / leaving the life you led / before we met

Roland may think he’s hunting Walter, but in King’s own opening to the story, he’s said to merely be “following.” While trying to end his enemy, he might be playing right into his hands.

RELATED: This Week’s Cover: Unlocking the film version of Stephen King’s 

The Gunslinger loathes Walter, blaming him for the loss of everything he has ever known or cared about, but McConaughey says The Man in Black doesn’t return the hard feelings.

him,” the actor says. “He’s really the only true adversary I have. I expose hypocrisies, and he’s the closest to pure there is. It’s his persistent, resilience to be good and altruistic. He’s very precious to me. I almost don’t want to see him go.”

Roland is helping this immortal keep pace. Using dark, crystal orbs in

tales that serve as windows between different times and places, Walter even finds himself communicating with his frenemy.

“So many times I’m just pumping him up, through sorcery, almost like the man in the corner of the ring for a boxer,” McConaughey says, breaking into a whisper: “’Come on … you can do this … stay in the game,’ because I want to keep him, I want to keep his vengeance to find me. I want to keep that very vital, you know? My want, my need, my mission is to bring down the Tower. My love, my adoration, my muse, my shadow, is Roland.”

For all its intricate mythology, multiple worlds, and contrasting genres, that’s the core of

. Good versus evil. A chase. A search. Friends and enemies discovered along the way.

At the end of the journey stands the Tower, which is the nexus point of all time and space, the place where dimensions meet – or fall apart.

Ours is one world within the tower, but there are many more than this. Whoever rules this edifice, rules all. Life. Time. Space. Everything.

And if it falls …? “All the gaps between the worlds are filled with blackness and evil,” McConaughey says, practically licking his chops. Imagine the walls of a zoo collapsing at the same time, except the creatures unleashed on humanity are demons, vampires, mutants and fiends from different planes of existence.

“Once I bring the Tower down, and take a seat next to the Crimson King, I’ve got my own plans from there as well,” McConaughey says.

In the image above, Walter strolls casually up the ramp of a place known as the Dixie Pig, a hideaway in New York City for bloodsuckers, spellcasters, and Taheen (humanoid, masked monsters), who are bowing in surprise – and no small amount of fear — before their master.

Walter has a master, too – the Crimson King, an insane, god-like entity who will be resurrected to rule the chaos of these collapsed worlds if The Man in Black can successfully shatter the Tower. You can see the king’s sigul – a glowering red eye – in the sign just above McConaughey’s head.

Walter wears the same symbol in a chain around his neck. “That’s the talisman of the king, yes, and nothing else,” McConaughey says, drawing the necklace out from his collar. “I didn’t want to be covered in accoutrements.”

Walter has ventured to the Dixie Pig in pursuit of a boy in our world named Jake (15-year-old Tom Taylor) who has a power known as “The Shine,” which can be harnessed to break down the trans-dimensional beams that keep the Tower standing strong. In this scene, he is dropping in on Richard Sayre (Jackie Earle Haley), a low man of high rank, who rules the Dixie Pig like the ambassador of an embassy of monstrosities.

Walter doesn’t think much of Sayre, but he’s actually happy to be here.

film starts, he’s actually rather… bored. Hanging out in another dimension at a place called Devar-toi, a Norman Rockwell-like neighborhood that keeps the captured psychics content until they can be enslaved to help blast at the Tower.

Walter hasn’t been making much progress.

“I’m at home base, Breaker Central, doing the daily ritual of choosing the children and running the break,” he says. “And we’ve been doing this for some time now, but we haven’t been able to bring down this Tower. We’ve shook the dust off it quite a bit, thrown a few boulders but haven’t found the right all-star with the shine to actually bring it down. So we go through the daily ritual of chopping down this proverbial tree.”

Jake wouldn’t be the first “Breaker” Walter has kidnapped. But he might be the last one he needs. Walter greets this discovery like a winning lottery ticket.

news!” McConaughey says. “One, this is what I need to get the job done. Two, it’s a field trip for me. I haven’t been down there in a long time. The Devil likes New York. Let’s go sing and dance and do some detective work and find the boy with The Shine and bring him back and use him!”

But Jake’s power has also led him to make his own discovery – there is a monster chasing him, yes. But in the distance, another figure may be the thing that saves him: a knight who looks like a sort of cowboy.

As Roland chases Walter and Walter chases Jake – the boy is pursuing the Gunslinger.

It’s a circle that’s drawing closing in on itself.

: Part I: Idris Elba on breathing fire into Stephen King’s Gunslinger | Part III: What the film changes (and keeps) from Stephen King’s books

on newsstands Friday, or buy it here — and subscribe now for more exclusive interviews and photos, only in EW.

Kristen Wiig and Seth Meyers ask each other for forgiveness

Rolling Stones frontman Mick Jagger expecting 8th child

How \'The Dark Tower\' film connects to Stephen King\'s other books

\'Kong: Skull Island\' director has massive plans for Kong

Michael Strahan and Jimmy Fallon play the football-like Facebreakers

\'Star Wars\': Mark Hamill teases Episode VIII dialogue

\'The Dark Tower\': Exclusive First Look Images

Emmy Nominations 2016: 35 Facts About the New Class

\'Suicide Squad\': Before They Were Stars

\'Legally Blonde\' costume designer Sophie de Rakoff on Elle\'s \'signature color\'