Die-hard Stephen Sondheim fans have a rare opportunity to get a glimpse of the artist as a young man in the Arlington Players' production of "Saturday Night," the Broadway legend's first musical.

The musical was written in 1954 but never staged until recently. For those who wish to wallow in everything Sondheim, it's probably a wonderful evening. For everyone else, not so much.

Long before Sondheim burst into public acclaim with his first hits "West Side Story" (lyrics) and "A Funny Thing Happened on the Way to the Forum" (music and lyrics), he wrote a musical version of a play called "Front Porch in Flatbush," written by Julius and Philip Epstein, the brothers responsible for the classic film "Casablanca." With this matchless pedigree, "Saturday Night" must be a sparkling example of American musical theater at its best, right? Well, no. Aside from a couple of pretty tunes, this show's main value is as a window into the mind of Sondheim while he was still formulating his approach to music that would later revolutionize Broadway.

Several songs are familiar to Sondheim devotees, having been pulled from obscurity for revues or compilation albums, including the lovely "What More Do I Need?" and "A Moment With You." But they are exceptions in a series of tunes either dull or overwrought and featuring stunningly banal lyrics. He actually rhymes "bagel" with "Conrad Nagel" and "appeal" with "schlemiel" in the forgettable number "In the Movies."

The story features a leading man who is an unlikable, crooked dolt and his love interest, a whining wet blanket of a woman. Director-choreographer Christopher Dykton has miscast the leads, assigning the roles to performers who are not up to their tasks while overlooking far more suitable performers languishing in the ensemble.

The musical, set in 1929, tells the story of a low-level Wall Street functionary named Gene (David Carney) who hopes to escape Brooklyn by making a killing in the stock market. As his neighborhood pals lament not having dates on Saturday night, Gene, delusional with his sense of personal grandeur, gets dressed up and sneaks into fancy places. He soon meets Helen (Emily Barber Capece), another poseur who seems to have little regard for him and frequently belittles his dreams. Eventually, she bleats, "I'm very, terribly unhappy about it, but I do love you." It really makes you want to break out the bubbly.

Carney and Capece stress the unpleasant, dreary aspects of their characters' personalities and struggle painfully with the vocal requirements of Sondheim's complex score. Gene misappropriates the money his buddies trusted him to invest for them, sells his cousin's car for quick cash and ends up hiding from the cops. The legend surrounding this show claims it was never staged because the original producer died. Maybe it was really because other producers actually read it.

Annoyingly, the first good song, "A Moment With You" -- which comes eight tunes in -- is wasted. The ballad is sung mostly by the silky-toned Richard Butterworth offstage, his voice made to sound as if it's coming from a scratchy gramophone recording, before Carney and Capece join in the gentle harmonies. The charismatic Allison Block, who is underutilized in a secondary role, leads the singing of an old-fashioned, catchy show tune, "One Wonderful Day," and also shines in the amusing "I Remember That."

"It's That Kind of a Neighborhood" is pretty and again capably dominated by Block. It's a harbinger of Sondheim's later mastery and perhaps the only song instantly recognizable as his.

Matthew A. Anderson, as Gene's buddy Dino, outshines all the male performers. With a wonderful voice and innate charisma, Anderson projects a likeable persona that would make the dour Gene much more bearable.

The production is well directed, generally well performed and looks good. Still, "Saturday Night," while interesting as theater history, is much less enchanting as entertainment.

"Saturday Night," performed by the Arlington Players, continues through May 22 at the Thomas Jefferson Theatre, 125 S. Old Glebe Rd., Arlington. Showtimes are 8 p.m. Fridays and Saturdays and 2:30 p.m. Sundays. For tickets or information, call 703-549-1063 or visit www.thearlingtonplayers.org.