In "Prom Night," now at 10 area theaters, "Friday the Thirteenth" meets "Saturday Night Fever."

A crazed killer, his face (or is it hers?) masked by a hood, stalks the corridors of Alexander Hamilton High School brandishing an axe and seeking blood, while oblivious students boogie merrily in the auditorium. The Avco Embassy film gives a grim, final touch to the "Death to Disco" movement.

"Prom Night" also brings a new dimension to the "kill the teen-agers" theme, which probably reached its highest point technically in "Friday the Thirteenth" -- because William Gray has given "Prom's script something resembling a plot and director Paul Lynch has infiltrated his cast with people who can act. The result is not quite so grisly in its death scenes as "Friday the Thirteenth" and not nearly so vivid in its music and dancing as "Saturday Night Fever." But it is more satisfactory as a movie -- which does not mean that it is really satisfactory as a movie.

Take the scene in which Lou, the school bully (David Mucci), gets it in the neck. This is the point where the crazed killer, who had previously been skulking in the shadows and concealing his handiwork, goes public. Lou is decapitated backstage in the auditorium with one stroke of the axe, and his head bounces out on the ramp that had been reserved for the grand entry of the prom king and queen. It settles there, the neck serving as a sort of pedestal, and glares reproachfully at the dancers, who sensibly run away screaming.

In Friday the Thirteenth," the beheading would have been done closeup, in slow motion, with bright lighting and a tightly focused lens. The audience (those who were looking) could have seen the dying gleam in Lou's eyes and the bristling details of his 5 o'clock shadow. In "Prom Night," it happens quickly and in semi-darkness; the audience knows what has happened but does not, so to speak, experience it. When the severed head comes to rest, it is shown only in long shots from angles that do not make it the focus of attention. It may be that the work of Warren Keillor (who has the curious title of "Prosthetis" in the film's credits) was not designed for close inspection, but one would like to think that some kind of artistic restraint was involved.

There is certainly restraint in the number of the vividness of the killings, although they seem quite numerous enough. Particularly noteworthy are a long cat-and-mouse scene, in which the killer stalks Eddie Benton (a promising young actress, one should note, in view of her first name), and a dramatic struggle between the killer and the driver of a panel truck which finally goes off a cliff in a technically pleasing burst of flame.

Death freaks may complain that, except for these scenes and a few others, the people in this film spend entirely too much time acting, and the plot give too much attention to the daily dynamics of high school life -- the kind of thing that people used to go to see in the movies. But the result is that one actually cares about the people who are being killed; they become more than raw meat.

Good and promising actors -- people who deserve a better film the next time -- are too numerous to name. Particularly notable, far down in the credits, are Robert Silverman, who makes much of the small role of Sykes, a creepy school custodian, and Joy Thompson, who provides some good comic acting until her untimely death. Among the stars in what must be the world's most mature high school class, Jamie Lee Curtis does a much better job of acting than one would expect of a daughter of Tony Curtis -- perhaps because she is also a daughter of Janet Leigh.