The Vietnam-veteran-as-stock-character is the Frankenstein monster in modern dress. There's no bolt through his neck, and the scars have moved from skin to psyche, but it's the same bit: The overweaning pride of modern civilization tries to build a superman and creates a monster. In the case of Vietnam, the attempt to create a heroic liberator gives us a psychopath, a walking time bomb. As a society, we fear him, we pity him and ultimately we have to destroy him, or at least drive him mad.

Tonight's version of this ever-popular tale is Tom Cole's "Medal of Honor Rag" on Channel 26's American Playhouse at 9. It's essentially a two-person play, with a third bit part. A black winner of the Congressional Medal of Honor, Dale Jackson, known as DJ, spends 90 minutes arguing, emoting and even threatening to fight with The Doctor, a psychiatrist, at a Veterans Administration hospital in Valley Forge, Pa.

DJ, played with as much virtuosity as the role can bear by Damien Leake, saw a group of buddies killed in a tank in Vietnam, and proceeded single-handedly to kill five to 20 of the enemy, in a fury described as purely pathological. He's in Detroit with a medical discharge 72 hours later, which seems unlikely. Civilian life turns into day after day of lying on his bed staring at the ceiling. Then he gets the Medal of Honor. He reenlists. Things go wrong, and he winds up in and out of VA mental wards.

The Doctor, portrayed by Hector Elizondo, tells DJ that the problem is "survival guilt," which he understands because he survived a Nazi concentration camp when others in his family died.

It's remarkable that the play succeeds as well as it does. Just as Frankenstein's scars are hidden, so the action is largely offstage, as narrated by the two characters. There's weeping and crawling and a chair-smashing frenzy, but they're mostly stagecraft. Their believability is a testament to the skill of the playwright, who is also skilled at handling the irony and ulterior tones required by the drama of self-revelation.

"What do I need you for?" asks DJ, near the beginning.

"I don't know," says The Doctor. "Maybe I need you."

Further on, DJ warns that he is, in fact, the epitome of the veteran as walking time bomb: "If I lose my cool, what is there to stop me from going out in the streets of Detroit and killing up everything I see?"

The requisite Vietnam atrocity gets fitted into a story DJ tells about a truckload of soldiers, led by a lieutenant, gunning down a group of children who make obscene gestures at them. They're nowhere near any combat when this happens, so it seems extremely unlikely, but that's not the point. We're dealing with a monster motif here.

It comes down to the Medal of Honor. Says The Doctor: "The medal makes a man sick, drives him into a hospital." Ultimately, it drives DJ into carrying a pistol into a grocery store. He wants to hold it up because he needs money to pay his wife's medical bills. But if he's on active duty, why isn't she in a military hospital? Anyhow, the store owner takes care of the survival guilt by putting five bullets in him.

"Medal of Honor Rag" probably plays better on stage than on TV--it's hard to understand why they can't show the events they only talk about. It makes a thin 90 minutes in any case.

It could well excite the ire of Vietnam veterans who are sick of being portrayed as nut cases, and of having their bravery denigrated as pathology, but the Vietnam veteran as fictional character has little to do with the ones in real life. He's just another in a long and popular lineage of mythical monsters and, justly or no, he isn't going to be shouted out of existence by cries of slander.