When the 18-year-old Scottish aristocrat Jay Cavendish (Kodi Smit-McPhee) falls for local girl Rose Ross (Caren Pistorius) he falls so hard he’s willing to pursue her across half the known world.

On his perilous journey from Scotland across the United States he runs into outlaw Silas Selleck (Michael Fassbender), a mysterious Irish stranger who shows up after a dust storm to aid our young hero in his love quest.

But something doesn’t add up. You want to believe that Selleck has his young friend’s interests at heart, but there’s something about this leathery cigar-chomping character in a worn out cowboy hat that won’t let you trust him completely.

And by the time you get to this point in "Slow West" (opening Friday), Fassbender’s wonderfully genre-busting new western, you’ll be as committed to finding out what happens as Cavendish is to finding Rose.

This is shaping up to be a remarkable year for 38-year-old Irish/German actor Fassbender, who has no less than six new movies opening this year. As of right now "Slow West" may be one of the best of them all. He plays a mysterious and handsome outlaw in a role that would once have gone to an actor like Clint Eastwood.

Currently Fassbender is filming "X-Men: Apocalypse" with Hugh Jackman and Jennifer Lawrence in Montreal so he’s not on a press tour for this smaller budget (but perfectly formed) new western, which his star power helped to get produced.

“I’m in a very privileged position that I can get a small film like that made,” he recently told the press. “The percentile, I don't know exactly what it is, but it's very small to be in the position that I'm in, in an industry like this. I’m grateful every day.”

Fassbender is too modest to add that he wouldn’t be in that percentile if the world’s top directors weren’t clamoring to cast him, aware of his gifts. But it’s a fact they’re lining up to with films like the biopic "Steve Jobs," in which he plays the legendary Apple founder.

Directed by Oscar winner Danny Boyle and co-starring Kate Winslet, "Steve Jobs" looks at how driven Jobs was to be at the forefront of the digital age, but there were costs to his family and some have even said to his health.

Also on Fassbender’s slate this year is "Macbeth" (which co-stars Ireland’s Jack Reynor) in Shakespeare’s deathless tale of ambition and murder. It’s an actor’s master class of course, and an ideal vehicle to remind the world, if it needs to be reminded, of his versatility as an actor.

To highlight his skill as a romantic lead in a drama there is also "The Light Between Oceans," the tale based on the bestselling book of what happens when an isolated couple decide to raise an infant who washes up near their lighthouse in a boat that also contains a dead man.

Fassbender plays Tom Sherbourne, the lighthouse keeper and a war veteran with his real life girlfriend Alicia Vikander playing his wife, the woman who disastrously persuades him that they should keep the little baby they name Lucy and say nothing of how they found her.

What could go wrong? Well, when they return to shore everything does. Hannah Roennfeldt (Rachel Weisz) turns up as the devastated mother of the child she now believes is dead and that forces the adoptive pair into a terrible dilemma. The film reunites Fassbender with Caren Pistorius, also seen in "Slow West."

This week, though, it’s Fassbender’s western that’s making the news and for a host of good reasons. First, it’s an unexpectedly riveting study of how far people will go to help themselves. Second, he gives a slow burn performance that surprises you with its subtlety, and third, the direction by newcomer John Maclean is top notch.

Unusually, Fassbender is allowed to speak in his own north Kerry via Dublin accent, and that only serves to make his character that bit more unknowable. Living far from where he was born with nothing left to lose makes him all the more unsettling, not less so.

At root "Slow West" is about what it costs to live with passion, and what it costs to live without it. Ask yourself when was the last time you saw a western that offered anything more than a few thunderous shootouts?

In "Slow West" we get to see how the west was really won in the 19th century with marauding hordes of Indian killers hunting down Native Americans at rifle point.

We also see how dangerous frontier life was for the rugged souls who live and die in this lawless hellscape. As poor teenage Jay ambles along in search of his lost Rose he encounters a Union soldier who’s as prepared to shoot him as any Native American.

Luckily, Fassbender’s Silas swoops in with an offer of safe passage and Jay gets to stay in one piece, but director Maclean is much more interested in the ways in which the old population of the country is being displaced and killed by the arriving settlers.

It’s rare to see a western so preoccupied by the rough work that was done to the indigenous people here in the 19th century, and the film is enriched by its inclusion.

Meanwhile, Selleck begins to form a bond with the young Scotsman he’s shepherding through the wilderness. They could not be more unalike. Jay believes that the world is filled with wonders, but Silas sees it as a mean and hungry place filled with desperate cutthroats who are waiting to scalp you for a dollar.

What happens between the pair of them is the heart of the film. Silas has been hardened by the world’s treachery, but there are pockets of decency and sensitivity that still remain in him, so Jay’s purity and goodness strongly affect him, undoing his worse nature and inspiring his better one.

The film concludes as it promises to from the opening scenes in a dramatic hail of bullets and Maclean directs the sequence meticulously, giving it a classic aura.

There are sequences that are laugh out loud hilarious in their irony and cruelty, but the overall message is one of sobering cynicism. Jay is a starry eyed young lover in pursuit of a girl who is as elusive as all the stars he knows by name.

By being this love struck there’s not much chance for Fassbender to play the macho man of few words, which is to the film’s benefit. Jay’s goodness unmasks the people around him.

Rose, the young woman Jay is devoted to, turns out to be the clearest eyed person in the film. She knows exactly what the men around her are like and she knows what they want from her. It’s why she’s still alive.

Because of her "Slow West" inches toward a deeply satisfying but unexpected new beginning, one that very few of the characters have a right to ask for.