If you’re not yet aware of the Grammy-winning Christian pop duo For King & Country, comprising brothers Joel and Luke Smallbone, “Unsung Hero” will introduce you to their folksy family lore, if not their musical successes. The film is a biographical drama about the Smallbone family, a large brood from Australia who immigrated to Nashville in the early 1990s, following father David’s dreams of working as a promoter in the music industry.

“Unsung Hero” is co-written and co-directed by Joel Smallbone (with Richard L. Ramsey) and he also stars in the film playing his own father, who eventually managed the music careers of For King & Country, and Joel’s sister Rebecca St. James. Their siblings work in the family business as managers, lighting directors and documentarians (they all make cameos in the film), and there’s a sense of can-do collaboration among the tight-knit Smallbone family. This theme runs throughout the film and it makes sense that Joel would undertake the telling of his family’s own story in such an intimate way.

Therefore, “Unsung Hero” is like a much more expensive extension of the camcorder home movies that serve as a running motif throughout. This isn’t just a music biopic or a family drama — it’s a presentation of a family narrative as told and embodied by the family members themselves. A valid endeavor, to be sure, but important context when considering the work as a cultural product.

Joel Smallbone is an appealing actor, even if it is a bit distracting that he’s portraying his own father (he has described the experience as a “therapy session”). Joel is also a character in the film, as a child (Diesel La Torraca), while Daisy Betts plays Helen, the Smallbone matriarch and Joel’s mother. Helen is, of course, the unsung hero of this story, the heart and spine of the family who insists on keeping them together while David makes one last-ditch attempt to make it in the music industry in Nashville. Betts is the emotional center of this film, her character unflagging in her determination, keeping spirits up as David’s dreams are slowly crushed.

The family of attractive Aussies arrive in the United States without a stick of furniture in their rental home, and they nest in beds of clothes while they get on their feet with the help of a couple from their church (Lucas Black and Candace Cameron Bure). They clean houses and landscape yards, clip coupons and accept the charity that comes their way, reluctantly, on David’s part.

While David struggles with the dampening of his dreams, his daughter Rebecca (Kirrilee Berger) is just starting to embrace her musical aspirations. But she can’t chase them until her father gets over his own deep hurt at being rejected by the industry. It takes him some time to understand the advice given to him by his own father, James (Terry O’Quinn), back in Australia, that his family isn’t in the way of what he wants. Rather, they are the way.

“Unsung Hero” follows a predictable narrative path of struggles and salvation, but it’s not a traditional music biopic — it doesn’t start with a record deal, it ends with one. The focus is on their hardships to get to that record deal, which is clearly what matters to filmmaker Joel Smallbone. It’s not the success, the Grammys, the stadium concerts, but the ways they stuck together, eked it out, allowed themselves to dream, all thanks to their mother, who never let David’s challenges get in the way of her kids’ imaginations.

It’s a humble story, one with the capacity to inspire in its simple message of perseverance. But the film itself, as an artistic product, feels limited in its observational scope, because the filmmaker doesn’t have any distance from the material. Smallbone is a fine actor, but alongside Ramsey, he’s a limited filmmaker. Their visual style is drab at best, and the storytelling lacks the kind of self-reflection that might elevate this project. As it is, “Unsung Hero” feels more like band merch than an insightful family portrait.

Katie Walsh is a Tribune News Service film critic.