Because of an error in the Kennedy Center program, a review of "Mail" in yesterday's Style section credited Antonia Ellis with playing the literary agent. The part was performed by Michele Pawk. (Published 2/20/88)

It is only to be expected that Stephen Sondheim, who has fashioned some of Broadway's most innovative and intelligent musicals, also has spawned a legion of imitators. But if imitation is the sincerest form of flattery, it can also make for truly disheartening theater. Few spectacles are more dispiriting than that of mediocrity trying to ape genius.

By way of illustration, let me point out "Mail," the new musical by Jerry Colker and Michael Rupert, which opened Wednesday night at the Eisenhower Theater. Everything about the show -- its themes, its score, its very eagerness to brave new horizons -- seems to have been borrowed from Sondheim. All that's missing is Sondheim's vast talent. By the end, so much unchastened pretention may well have you screaming for relief.

With a relentlessness that borders on the maniacal, the creators of "Mail" have taken the nugget of an original idea and proceeded to drive it deep into the ground. In the prologue to the evening, Alex, a 29-year-old aspiring novelist in the grips of "Monolithic Madness," walks out on his lover, his best friend, his family and a stalled career. Flash forward. Having nursed his soul in the mountains of Vermont, Alex returns to his Manhattan flat to find four months of mail on the doorstep.

As he sorts through the accumulation of personal correspondence, unpaid bills and the usual amount of junk mail, the sundry missives spring to life. Or at least, the people who wrote them do. As if in a bad dream, they pop out of the refrigerator, surge through closed windows, drop down from the ceiling and slither out of the leather couch. Each letter occasions a musical number, which serves to define the plight of poor, confused Alex.

Like Bobby, the bachelor in Sondheim's "Company," he is having trouble committing to a relationship. Like the painter Georges Seurat, haunted by the implications of an empty canvas in Sondheim's "Sunday in the Park with Georges," he finds himself paralyzed by the blank page. What's more, his father is importuning him to come home and work in an auto supply shop. His predatory literary agent wants to lure him into bed. His best pal is accusing him of selling out on their longstanding friendship, while his pregnant girlfriend is whimpering like an abandoned puppy.

As if that were not enough (and it is, believe me), a trio of magazine pitchmen try, in a ditty of transparent symbolism, to get Alex to subscribe to Life. Later, a contingent from the power company, dressed in T-shirts and hard hats, informs him that "We're Going to Turn Off Your Juice," and in the process momentarily transforms the apartment into a discothe`que. Still later, the spangled representatives of a million-dollar sweepstakes bombard him with instructions for winning the big jackpot.

Can Alex patch up his relationships and get his head together? Will he resist easy success and remain faithful to his artistic integrity? Will he discover his true feelings? For mercy's sake, will he ever stop singing the "Ambivalent Rag?"

The fact that in the age of the telephone and the answering machine no one bothers with letters anymore is the least of the show's problems. Far greater is Rupert's score, which wants to be all things to all musical tastes -- running the gamut from soft rock and country western to ragtime and the blues. But while a composer like Sondheim can elevate pastiche to art (see "Follies"), Rupert is always coming in way under his models.

Colker's lyrics are no better; they seem to have been written by the token intellectual at the Hallmark Greeting Card Co. The stabs at triple rhymes and intricate wordplay (that's the Sondheim influence again) do little to mask the banality of the sentiments being expressed. One of the rare spoken lines may best serve to indicate the general level of this endeavor. Speaking of his father, Alex observes that his life "is like a blue-collar version of an Ayn Rand novel: 'Atlas Burped.' "

In addition to his composing chores, Rupert plays Alex, and there is rarely a moment he is not on stage. Not only has he given himself a generous portion of numbers, but he usually chimes in on most of the others. There is in "Mail" the same sense of suffocating egotism that you find in Anthony Newley's musicals, which served principally to showcase Anthony Newley. (You might describe "Mail" as Rupert's attempt to tailor himself a "Stop the World -- I Want to Get Off.")

Newley, however, had a certain pluck and charisma going for him. Rupert is bland and unappealing (and very much on the wrong side of 29). He interprets his songs with the earnest fervor that only a composer could muster for them. When not singing, he adopts an expression of hemorrhoidal angst and gazes painfully into space. The supporting players consistently overexert themselves -- knowing full well, I guess, that if they don't score quickly, they'll be shunted aside for more of Rupert.

As played by Mara Getz, Alex's plaintive girlfriend brings to mind the offspring of a barfly and a cockatoo. Antonia Ellis, the man-eating literary agent, has legs for days and talent for minutes. Robert Mandan, Alex's father, gives the impression that he just wandered in from a recently canceled TV sitcom and is still looking for his bearings, not to mention the key to his songs. Only Brian Mitchell, as the best friend, performs with any semblance of ease and style. Maybe he should be playing Alex.

Like an interior decorator on speed, director Andrew Cadiff has dressed up every square inch of the show with gimmicks, sleights of hand and special effects. The big question in Act 1 is not Who Is Alex and Why Is He Going Around the Bend? Rather, it's How Many Different Hiding Places Can This Production Invent for the Letter Writers in Alex's Life?

In Act 2, the set revolves on a turntable, and Alex's cluttered apartment is replaced by a stark all-white flat. (Alex, you see, has decided to wipe the slate clean!) Before long, however, a series of semiabstract slides are projected onto this immaculate surface, and Alex is grappling with his anguish all over again.

For a while, the sheer volume of activity may distract you. The pairs of colored slippers that dance a soft-shoe on the staircase all by themselves are not unamusing. The chorus girls are pert and shapely, although it seems cruel to include in their number one who is patently overweight. "Mail," however, never lets up on the tricks and the reason is apparent. Underneath the hoopla lurks the tiresome and cliche'-ridden saga of the sensitive young man in quest of himself.

I can't say you'll care for Alex, which makes it doubly difficult to care for "Mail." At great effort and no small financial cost, the musical succeeds only in giving cleverness a bad name. Stamp it "Return to Sender," folks, and browse through the L.L. Bean catalogue instead.

Mail, book and lyrics by Jerry Colker, music by Michael Rupert. Directed by Andrew Cadiff. Scenery, lighting and projections, Gerry Hariton and Vicki Baral; costumes, George T. Mitchell; choreography, Grover Dale. With Michael Rupert, Antonia Ellis, Mara Getz, Robert Mandan, Brian Mitchell. At the Eisenhower Theater through March 19.