Sometimes a gimmick turns out to be more than just that. Such is the case with MetroStage's summer production of the musical "The Last Five Years." The three-year-old off-Broadway hit, which tells the story of a relationship -- highlighting courtship, marriage and dissolution -- is transformed from mundane to interesting thanks to a trick of storytelling. Writer and composer Jason Robert Brown has his two characters tell their relationship history in opposite order from each other. She begins at the sad ending; he starts at the hopeful beginning.

The only times they are close to being in tandem are mid-relationship at the time of the wedding, and at the end of the show. What would otherwise be a mundane tale presented entirely through songs, both ordinary and compelling, seems fresh as the mounting sense of irony and inevitability that comes from knowing how the story ends colors audience sentiments.

Of course, none of that would matter if the two performers who constitute the show's entire cast weren't superb, and they are, particularly Tracy Lynn Olivera as Catherine. We first meet Catherine as a heartsick woman mourning the end of her marriage. Olivera starts off the show on a high emotional pitch, her magnificent voice soaring in the elegiac "Still Hurting."

By contrast, Mark Bush's Jamie follows that by strutting onto the stage full of optimism and energy as he exults over a new love interest in the lighthearted "Shiksa Goddess." The transition may be a bit jarring and Bush may have trouble finding the right energy level early on, but he eventually hits his stride and this chamber musical begins to click.

The 16 songs are a collection of contemporary pop expressions with often poetic, sometimes dramatic, sometimes witty, lyrics. Olivera and Bush are accompanied by musical director Howard Breitbart on piano, leading a small, eclectic ensemble of musicians on cello, guitar, violin and bass. Directed by familiar local performer Jane Pesci-Townsend, this is a down-to-earth production, with nothing fancy in the way of sets, lighting or costumes. The staging is simple, and the focus is on the characters.

Catherine and Jamie are not larger than life. In fact, particularly as portrayed by Olivera and Bush, they are rather schlubby. Catherine is a struggling actress, while Jamie finds success as a novelist, and their divergent fortunes aggravate the faults in their personalities and the fault lines in their relationship.

The highlight is Olivera's tour de force performance in "Climbing Uphill," as Catherine auditions for a summer stock role. It's a demanding vocal exercise, with the character entering a stream-of-consciousness reverie that transforms the number into a rapidly paced "patter" song.

Another strong segment comes with "The Next Ten Minutes," as the couple comes together, literally nose-to-nose. It's a love scene tender enough to cause a few audience sniffles, especially as we know this emotional bond is tenuous, the characters passing each other in different directions.

MetroStage has been pulled inexorably to lighter musical fare in recent seasons to fill seats, often crossing over the line from theater into cabaret in order to keep the lights on and the doors open. The shows that are more supper-club than theater -- such as this past winter's "The All Night Strut!" -- do sell tickets. By contrast, the Alexandria company's most recent drama, the critically acclaimed and gripping "Sophocles' Electra," had to shut down early.

"The Last Five Years" may seem like light cabaret fare, but whether it has to do with Pesci-Townsend's direction, or the emotional heat generated by Olivera and Bush, or the way in which the story arcs heighten the poignancy, this is definitely a theater experience and, while rather brief at 90 minutes, a satisfying one at that.

"The Last Five Years" continues through July 24 at MetroStage, 1201 N. Royal St., Alexandria. Showtime is 8 p.m. Wednesday through Saturday,and 2 and 7 p.m. Sundays. For tickets, call 800-494-8497 or go to www.boxofficetickets.com. For information, visit www.metrostage.org.

Mark Bush and Tracy Lynn Olivera in MetroStage's production of "The Last Five Years."