“It’s been a long wait,” writer/director Jeff Nichols says about his upcoming film “Mud,” and indeed it has, on so many levels.

The film first screened at the Cannes Film Festival nearly a year ago, where it was picked up by Roadside Attractions for domestic release. But rather than risk it being lost in the fray by trickling screenings throughout the fall festival circuit, the indie distributor held on to it. The film, which stars Matthew McConaughey (in the thick of a career renaissance), was brought back into the light at the Sundance Film Festival in January as Roadside primed it for a late-April release.

Its roots, however, stretch back so much farther, to Nichols’ days as a film school student at the University of North Carolina School of the Arts in Winston-Salem, North Carolina. It was a girl breaking up with him in high school that got him thinking on the film’s themes of romance. “It’s one of the lamest reasons that you sit and write a movie,” he admits, “but that level of heartbreak from your first love, even if it is puppy love, is pretty intense. Just because you’re young I think people dismiss those emotions and those feelings, but I think that might be unfair. Look at Romeo and Juliet. They were in their teens.”

So when Nichols first started turning over the idea of what would become “Mud,” he wanted to write something with an arc that would reflect that sort of intensity. Interestingly enough, though, way back there in college, Nichols already had his actor in mind. Yes, “Mud” was written for Matthew McConaughey over a decade ago.

Like any budding film fan, Nichols had seen and loved Richard Linklater’s 1993 comedy “Dazed and Confused,” which first put McConaughey on the map. But it was John Sayles’s 1996 indie drama “Lone Star” that really attracted him to the actor and what he was capable of. “I was just like, ‘Yes. I want that guy,'” Nichols says. “This is in 2001. I remember being home on a trip from school and I was talking to somebody. She was like, ‘What are you doing right now?’ This is back in film school when you wanted your friends to think you were not just some bum film student. I was like, ‘I think I’m writing something for Matthew McConaughey.’ Cut to 10 years later and I’ve gone my way and he’s gone his way and it’s just somewhat serendipitous that we’ve dove-tailed into each other.”

Indeed, McConaughey has been enjoying a second wind in his serious acting career after a detour into conventional commercial vehicles like “Failure to Launch” and “Fool’s Gold.” That’s “mailbox money,” as the actor has jokingly called it (referring to residuals). But lately, he’s worked with true artists like William Friedkin (“Killer Joe”), Lee Daniels (“The Paperboy”), Steven Soderbergh (“Magic Mike”) and Martin Scorsese (“The Wolf of Wall Street”), in addition to Nichols. He’ll likely be in the awards conversation later this year with “Dallas Buyers Club,” “Mud” and maybe “The Wolf of Wall Street,” and he was recently tapped to head up Christopher Nolan’s next film, “Interstellar.”

Getting back to “Mud,” Nichols’ thought process soon led him to considerations of mentorship, which fleshed out the story even more, feeding on other things that were very much in his mind coming out of college. “I was starting to walk on my own legs a little bit and figure out what kind of storyteller I was going to try and be,” he says. “I had a lot of mentors, and a few really solid ones, but I started to pick away at some of their faults. And that’s what the movie is about: false mentors.”

The film is also about a style of storytelling Nichols is fond of, he says. He wanted to embed a magical realism element, touching on ideas found in southern folklore, superstitions, etc. The presence of snakes, for instance, is as much a superficial obstacle as it is a subtextual commentary that leads back to those ideas of mentorship. “I wanted that in the story because it speaks to a bigger mythology,” he says. “It’s not uber-realism, which is something I dealt with in ‘Take Shelter,’ because it was going to be grounded, and exacerbated, by the point of view of a 14-year-old, not the point of view of a guy in his mid-30s struggling with the economy.”

In a word, it was the unknown that Nichols says he wanted to lace throughout. There is something exotic about some of its imagery — a boat lodged in a tree, for instance — that helped carry across the perspective of the film’s young protagonist, Ellis (played with staggering confidence by young Tye Sheridan). “These are things that could be fantastic and maybe true,” he says. “They don’t necessarily feel like they could be true, but you don’t know any better. So maybe they are. All of that felt appropriate.” And particularly so in a story about young love and all the mysteries that come with it.

In the final analysis, the whole process was “tricky,” Nichols says, because it was all so tied to that perspective. “It’s arguably dangerous to write a movie that way,” he says. “But I wanted to see if I could pull it off.”

“Mud” opens in theaters Friday, April 26.