One of the dangers in staging a production that’s equal parts rock concert and musical theater is ending up with the worst of both. The world premiere of “The Sound of the Guns,” now playing at the Firehouse, only barely avoids that fate thanks to a few powerful scenes and one exceptional performance.

The show highlights the work of Church Hill songsmith Jim O’Ferrell, who has put out six studio albums with his band, the J.O.B., since he was honorably discharged from the U.S. Army in 2008. O’Ferrell and crew run through a dozen of their songs in the course of the show, from the power-pop balladry of “Messenger” to the straightforward blues-rock of “Broken Heart.”

Interspersed between the songs are interconnected scenes depicting three soldiers serving in Iraq in the first act, then shifting to their post-deployment lives in the second act. A narrator (cryptically listed as “The Promoter” in the program and played by Mike Fletcher) provides scene-setting background while also interacting with O’Ferrell, making requests for the band to play certain selections.

The soldiers’ narrative starts with a charming foundation as Sergeant First Class Jack Duncan (Alex Harris) teaches two squad members, Staff Sergeants Bobby Flores (Enrique J. Gonzalez) and Antonio Frazier (Tevor Lawson), how to play guitar while killing time on base in Baghdad. What then unfolds is an unfortunately familiar tale of various tragedies, major and minor, having to do with reintegration after returning home.

The theatrical aspects of the production can be woefully awkward with too many clunky questions and “do you remember that time when …” examples of telling rather than showing. There is also too little connective tissue to establish more than a 2-dimensional understanding of the characters.

Amidst those flaws, Lawson’s visceral depiction of his character’s journey manages to invigorate the production and provide some bracing realism. In the short slices given over to it, his wariness of, but aching need for, his battlefield buddies’ assistance infuses a welcome vitality into the proceedings.

The hand-off between J.O.B. performances and the dramatic scenes generally work fine. But songs in the best stage musicals are more than just sonic adornment, they also advance the story or deepen the audience’s understanding of the characters. There is little of that here.

Director Joel Bassin deserves credit for heightening an electrifying synergy in scenes where the action gradually transitions into the band’s performance, the best example being an on-base talent show. Duncan somewhat sheepishly agrees to play in the show and, as he digs into the anthemic mid-tempo rocker “In the Night’s White Noise,” the band takes over and elevates it to wall-rumbling heights.

The scene also allows Harris to step away from his straightlaced character’s trajectory a bit and demonstrate some range.

From a purely musical standpoint, the J.O.B. acquits itself nicely. After starting off with a few middling numbers, it hits its stride midway through the first act with “Thrill Of It All.” Drummer Ronnie Thomas and bassist Craig Babich step up to pound out a rollicking foundation to what becomes a satisfying jam.

Guitarist Jason Crawford is best when he breaks out of the restraint imposed during much of the set; he delivers searing solos on “Thrill Of It All” and “Glory Never Comes” that made me want more. O’Ferrell has a solid voice that sometimes drops into a satisfying growl but doesn’t quite soar when his more impassioned compositions call for a Bono-style howl.

A downside of the show’s structure is that it forces O’Ferrell to stand aloof from the dramatic action that is based on his experiences. His songs may offer commentary or context but, as per most rock performances, the lyrics are not consistently clear enough to get much nuance.

“The Sound of the Guns” can sometimes feel like a jukebox musical for an artist you aren’t familiar with. But at its best, it uses the energy of a talented band to innervate a somewhat underdeveloped story about veterans and their challenges.

“The Sound of the Guns” runs at the Firehouse Theatre through July 14. Tickets are available at the Firehouse website.