Argument, that wretched cast-off of the modern drama,ought to get a Tony Award for Comeback of the Year.

Brian Clark's "Whose Life Is It, Anyway?" comes out with its forensic fists flying, and never stops throwing punches from the opening bell until the final knockdown. The fight is neither so simple nor so flimsily rigged Bernard Pomerance's "The Elephant Man," but this odd and wonderful play raises a cloud of challenging questions and allows its characters (and audience) the old-time luxury of taking sides.

Written by an American now settled in England, the play chronicles the career of John Merrick, a grossly deformed Englishman (probably a victim of neurofibroma, it is now thought) who has rescued in 1886 from a traveling freak show to become, with a charitable surgeon's help, a figure in London society.

At first, the dutiful Dr. Freddy Treves (Kevin Conway) has a hellish time finding a nurse who can stand the sight and smell of Merrick. One candidate runs shrieking from his room despite her vast experience with "lepers in the east." So Treves has the brainstorm of hiring an actress, Mrs. Kendal, who braces herself by recalling, instead of lepers in the east, an unpleasant actor who once played Antony to her Cleopatra in Brighton.

This turns out to be more useful training. Mrs. Kendal finds it strategically necessary to avert her eyes from time to time, but she exudes stage charm throughout her introduction to Merrick, and at its end, rejecting the suggestion that she attempt to shake his relatively undeformed left hand, she grasps the unrecognizably bulbuous formation situated where Merrick's right hand ought to be. "I am very pleased to make your acquaintance, Mr. Merrick," she says.

That handshake shows that gentle stuff a powerful moment can be made of when an audience is really wrapped up in a play, and the surrounding scene - with its suggestion that pretense can be a useful first step toward overcoming disgust - will probably have actors salivating to appear in revivals of "The Elephant Man" for years to come.

Carole Shelley, a flashy actress playing a flashy actress, deserves a significant share of the credit for the effectiveness of that scene. But even here, doing her best work, she has begun exhibiting a fondness for the meaningful pause that, by mid-act-two, has developed into a passionate love affair. Not since Rosemary Woods has anyone made such a specialty of inserting gaps into conversation.

As Dr. Treves, Kevin Conway is short, stocky and martial, and he, too, could hardly be more suitable at first sight. But as the play progresses - and begins to emphasize Merrick's influence, an an innocent romantic, on the demands on Conway that he seems unable to meet.

Shelley's over-acting and Conway's under-acting could confuse the daylights out of a far more experienced colleague than Philip Anglim, who plays Merrick, but throughout their scenes together, Anglim seems anything but confused. As un-elephantine an actor as you can imagine, Anglim approximates Merrick's deformities with a few contortions of limb and voice, and shows a spectacular ability to summon up depths of feeling through layers of surface affection.

When two hospital orderlies are fired for gawking at him, Merrick is troubled. "Had all that stared at me been sacked, there'd be whole towns out of work," he points out politely. Anglim makes this primitive wisdom elegant and convincing, and there is a subtle layer of doubt under his words when, on Treves orders, he repeats the doctor's proposition that "Rules make us happy because they are for our own good." But Conway, who should have his own underlying doubts, seems content to play the surface of his character.

The theme and story are so strong that even with some problems of execution on the acting end, "The Elephant Man" is thrilling theater. Transplanted from an east side church to Broadway, it has become one of the season's hottest tickets. Desperate theatergoers can regularly be observed loitering outside the Booth Theater at curtain-time pleading for an unwanted seat - but of course there are no unwanted seats.

Not only is the argument of Pomerance's play less bald than that of "Whose Life Is It, Anyway?" but the two works (both nominated for Tony Awards) come down, to some extent, on opposite sides of the same question. If a man totally paralyzed from the neck down has cause to take his life, after all, why not someone apparently exiled from humanity by sheer ugliness?

The blabbering characters who preach survival to the protagonist of "Whose Life . . .?" (Tom Conti) are simply no match for him. Perhaps what he and his play needed was a deathbed visit from the Elephant Man. CAPTION: Picture, I.M. Hobson and Kevin Conway in "The Elephant Man." AP