Over its last few seasons, the Pittsburgh New Music Ensemble has come tantalizingly close to truly achieving a complex, new style of theatrically-minded performance. Friday night at City Theatre on the South Side, it was Tantalus himself who put the group over the hump in the premiere of "Just Out of Reach," a smart and moving original production co-written by Kevin Noe and Kieren MacMillan.

Founded by composer David Stock in 1976, PNME began as a quintessential contemporary-music ensemble, one that performed, well, concerts. It still primarily performs compositions, but, since 2000, visionary leader Noe has gradually woven visual and dramatic threads around the music for more continuous presentations. On some occasions, he has moved the group a step beyond that, to "theater of music" endeavors, most of which have been satisfying artistically (including MacMillan's own "Drunken Moon" of 2006 that played off Schoenberg's "Pierrot Lunaire").

But there is no question that "Just Out of Reach" stretches far beyond anything the contemporary group has done before. It's essentially arty musical theater, with hearty doses of humor and pathos. The temptation would be to compare it to works such as Peter Maxwell Davies' "Eight Songs for a Mad King," but really it's better to let PNME's bold move into the realm of shows speak for itself.

The plot is simple enough. In the underworld of Greek mythology, the gods (played by the ensemble musicians, barefoot and clothed in red robes) take pity on three tragic classical characters -- Narcissus (sung by tenor Robert Frankenberry), Tantalus (baritone Matthew Romantini), and Sisyphus (Noe) -- offering them the option of suicide as relief from their deliciously ironic sentences. After countless pushings of a boulder up a hill or reaching for fruit and water, one might think they'd do anything to end their struggles. But, one by one, the condemned reject suicide.

But the twist here, inspired by Albert Camus' essay, "The Myth of Sisyphus," is that the three doomed -- and in this production insane -- characters are metaphors for humanity. I supposed a classical scholar may chuckle smugly about how obvious this is, but to those of us who don't think about Greek mythology on a daily basis, it was revelatory. In a sense we are all trapped in a world of repeated tasks -- some pleasurable, some torturous --and we chose to accept them as life.

That heady description was driven home with superb artistry and timing in the production. MacMillan's music oscillated from atmospheric, almost background to engaging, playful quotations of pop culture and full-on operatic expression. The latter's high points came in three gorgeous arias sung with a passion-drenched voice by Frankenberry, who constantly stared into a LCD screen bearing his video image. Lush and Romantic in style, these statements revealed the sincerity of Narcissus' love for himself.

Using pseudo Tai Chi in his pursuit of sustenance, Romantini's Tantalus was appropriately austere and troubled as the man who serves his son up in a stew for the gods. The son here was played by David Skidmore, a percussionist who supplied narration for the play.

Skidmore's versatility on stage was impressive, but it was Noe's creation of a joke-cracking, Shakespeare-quoting and generally mad Sisyphus that stole the show.

Amid goofy puns and a hilarious swing tune using a ventriloquist's dummy, it was in his part that the core of the work was most convincingly put forth.

Sisyphus not only didn't want the suicide solution, he didn't want to be bothered by the proposition.

He is simply too busy at his own "pursuit of happiness," no matter that he (and his boulder) never quite makes his goal.

The message to me is that you can't judge what another's life is like. Sisyphus' plight looks like hell to us -- and to the gods, who put him in the underworld -- but to him, it was life as he knew it.

Who is to say we are any different? Religious convictions notwithstanding, all we really can do in life is take seriously the situation we are in and do the best with it.

The only major criticism of the one-hour show is that it ended abruptly and could easily have examined these thoughts for another half-an-hour.

This week, PNME takes "Just Out of Reach" on tour to the Edinburgh Festival Fringe, where it will play 17 times.

But one gets the feeling that, even as it flies overseas, PNME has already lifted off into a compelling new realm.