When a play is going to consider the implications of what little boys and girls do at five in the morning when Papa is asleep, it is generally sophisticated or moral. Debut attempts, and fails, to be the former, and has a careless disregard for the latter. The result is an innocuous bit of piddle, diffuse in conception and dull in execution.

Playwright Mary Drayton has tried to exploit the traditional Southerner's predicament in a time when deep-seated customs must die in face of social progress. She has brought to this situation the modern, probably Yankee assertion, that it's quite proper to mess around sexually with someone before marriage, the better to suit one's mate later. The two require a good deal of delicacy in treatment, particularly if the play has no moral resolution. Unhappily, the makers of Debut have used a heavy hand.

Southerners will undoubtedly be offended at the play's vision of them--naive, stupid, raucous, and unable to master their own dialect. There is not a Confederate in the cast. Yankee morals triumph, the plantation's only virgin is corrupted, and tradition falls. Northern gag men must sparkle to get away with this; they don't, principally because the comedy has a minimum number of funny lines. Any Jackie Gleason fan can predict virtually every ensuing speech.

The admixture of comedy and farce, which destroys utterly the few intelligent, sophisticated bits, probably can be blamed on the cast. Director John Gerstad has taken a salon comedy and turned it into a circus-tent shriek show. Practically every player, with the exception of Tom Helmore, the seductive, Northern journalist, over-acts.

Helmore's realization at the end of the play that there are worse things in life than an untouched debutante seems quite convincing. His problem with accent is alarming; allegedly proper Bostonian and Harvardian, his dialect would place him somewhere between Trafalgar Square and Whitehall. But he is agreeably suave, unfaltering, and journalistic. Inger Stevens, the innocent partner, is difficult to confine on one theatre stage. While she must be obstreperous, she loses control completely. She is pretty, though, and in frank talk with Helmore is quite expressive. G. Albert Smith, as her father, has lost all Southern restraint in his attempt to represent the bulwarks of dogged tradition. He noticeably loses his Southern accent in conversation with Helmore, the play's only Northerner.

The comedy undeniably has four or five funny bits. With addition, revision, and some restraint, Debut might well suit Broadway tastes.