“I’m always on the lookout for interesting characters that suggest a world,” says John Carney, the director behind music-driven films like Once and Sing Street.

Having dedicated himself to being a cinematic chronicler of music and the people who make it, Carney has carved out a unique in-between space as a storyteller. A self-professed “failed band guy,” he picked up a camera and focused it on his onetime creative passion. Carney is a musician’s filmmaker; a bard for the bards.

After breaking out with indie Once, a movie about an Irish busker and a Czech immigrant pianist recording music together that landed an Oscar for best original song, he made movies about the second chances made possible by music (Begin Again), the triumph and torment of first bands (Sing Street) and the therapeutic prospects of a guitar (Flora and Son). Now, he is heading back to theaters with Power Ballad, out in a limited release on May 29 before expanding nationwide on June 5.

The character that inspired Power Ballad was a 40-something dad in a Dublin suburb that the director happened to spot one day. He was wearing leather boots, carrying a guitar and semi-successfully loading his daughter into the backseat of the family car. Says Carney, “He had the walk of a rock star, but like a rock star for whom it hadn’t happened.”

“He was just this guy who just kind of does what every writer is looking for, which is just throw a ton of questions at you that you need to answer,” Carney tells The Hollywood Reporter. “When did he say, ‘I’m okay with not being Bono?’”

With this in mind, Carney, along with his co-writer Peter McDonald, created Rick, a onetime touring rocker who, on a stop in Dublin, met the love of his life, settling down with a wife and daughter and a new gig as the frontman to a modestly successful wedding band. Overall, Rick is content, if not fully satisfied with his life’s trajectory.

Carney wanted to put Rick in conflict with a person who had the outward trappings of a life that Rick dreamed of for himself. Enter Danny, a massively popular former boy band-er having his own existential crisis, trying to figure out his next creative step as a solo artist. They come together during an alcohol-fueled jam session, after which Danny turns one of Rick’s songs into a chart topping hit, setting Rick on a quest to track down Danny and claim the credit he feels is deserved.

The storytelling potential of Rick and Danny’s juxtaposing circumstances appealed to Carney. He says, “I thought it was really interesting to meet a younger version of yourself and to give that person advice and to tell them what you had learned. But, the funny thing is, the person that you’re talking to is doing better than you.”

Early on, Paul Rudd was attached to play Rick. When looking for his Danny, Carney was aiming for a certain level of real-life musical bona fides. He explains, “Paul playing a singer in Ireland is already a slight push, but it’s one that the audience will allow. I can’t ask them to do it twice.”

To Carney, it’s a hard to find an actor that can convincingly play a musician who has reached the most rarified spaces of musical success. “A film, which will remain nameless, came out and it had an actor playing a singer, and it was so bad. Clearly, this actor was acting out what it was like to be a boy-band guy. And he was a good actor! So, it wasn’t that,” the director says.

Finding an actor who also happens to have spent a fair amount of time as an uber successul musician is a difficult task. But, with this ultra-specific remit, the ideal casting became clear.

“Nick Jonas has an inner working that’s going on all the time. He’s inscrutable,” says the director of the longtime singer-songwriter, whose acting credits include the Jumanji film franchise. “He brings a certain kind of mysterious, enigmatic reality and truth to the character that we really needed.”

Even still, Carney was told it was a “bad idea” to cast Jonas, who came-of-age as one-third of the pop rock bank the Jonas Brothers. He explains, “A lot of people in Ireland did think that there’s something a little bit novelty about the Jonas Brothers. European audiences are a little bit more precious.” Others warned the director that Jonas’ presence could overshadow the film.

By the time everyone was on set in Dublin, the filmmakers knew they had made the right casting choice. “Nick played this character really small. He didn’t come in going, ‘Hey, I’m the boy band guy!’ Then you realize that’s what those guys — those superstars, since they’ve been seven years old — have. It’s quiet,” Carney adds. “He wants to go and play golf and have a nice whiskey and talk about the part and go to bed early and call his daughter and his wife. That’s what being a massive boy band star is like, really.”

Film critics at SXSW, where Power Ballad had its U.S. premiere this March, took note of Jonas’ performance. “You don’t have to be familiar with Jonas’ actual career as a pop star to be dazzled by Danny’s innate magnetism,” reads The Hollywood Reporter’s review.

Watching Power Ballad, audience sympathies toggle back-and-forth between Rudd’s Rick and his quest for credit and Jonas’ Danny, with his desire for legitimacy. “Nobody is fully the person that they wanted to be in a way,” says the director, who pauses before adding, “Actually, except rock stars.”

Check out Paul Rudd and Nick Jonas as Rick and Danny in the latest trailer for Power Ballad below.