"Bad Boys" echoes the title of an infinitely superior television documentary by Alan and Susan Raymond on the subject of juvenile criminal offenders.

In the early stages of this bloodthirsty fictional movie, opening today at area theaters, there are flickering indications that the filmmakers might have intended something in the starkly authentic vein of documentaries like "Bad Boys" and "Scared Straight."

By the fadeout their work has degenerated into such a cesspool of Big House cliche's that you wish someone had been around to scare or shame a little sense into producer Robert Solo, director Richard Rosenthal and writer Richard Di Lello.

Sean Penn, who made an amusing impression last summer in "Fast Times at Ridgemont High," never comes close to loosening up in his role as delinquent Mick O'Brien, ostensibly the baddest of the boys who graduate from mean environments in Chicago to the cellblock of a juvenile prison in the countryside.

Mick is introduced in ultradynamic fashion, smashing in a car window to snatch the driver's purse and then mugging a gent who has the temerity to pursue him up a dark alley.

Not exactly endearing, and Mick's character profile isn't particularly enhanced by the discovery that he has a slutty mom and a nice, devoted girlfriend (Ally Sheedy) who lets him sleep over and dreams of a better life. "Don't dream," Mick advises, exiting her bedroom on the way to the caper that lands him in stir for the first time. An attempted rip-off of two rival teen-age gangs (the blacks and Latins), it ends with Mick's buddy Carl (Alan Ruck in a rather convincing impression of a jittery, mentally defective young felon) shot to death and Mick responsible for the death of a little boy he runs over trying to make his getaway.

The exposition remains just as expedient once Mick is behind bars. Far from evolving into a movie that examines a contemporary prison society, like "Short Eyes" or "On the Yard," "Bad Boys" leaves you utterly bewildered about the way things are supposed to work in the institution Mick inhabits.

The general idea is obviously dog-eat-dog, but it's depicted in ways that convince you of nothing so much as the filmmakers' obscene dependence on brutality.

The figures of authority, played by excellent, underrated actors like Jim Moody and Reni Santoni, appear to be tough-minded, capable jailkeepers who know what's what and speak to the kids straight from the shoulder.

However, to get things stirred up among the inmates, the filmmakers immediately contradict this impression of the authorities by showing the cellblock being tyrannized by a sadistic twosome (Clancy Brown as the white one, Robert Lee Rush as the black one), who seem to be the last guys on the premises who'd qualify for trustee privileges. Beating them up evidently earns Mick the right to inherit their privileges.

Since Mick is mysteriously exempt from challenges to his bossdom, the filmmakers kill time until they can trump up a challenge from the outside. The principal time-killing device is Eric Gurry as Mick's roomie, Horowitz, a brainy Jewish kid who landed in prison for rigging a bomb to get even with his enemies.

The challenger has been loitering on the sidelines since the start of the movie--Esai Morales as Paco Moreno, the hoody older brother of the kid Mick ran down. It's obvious that nothing of consequence is going to happen until a pretext is found for getting Paco and Mick in the same cellblock. This is accomplished in a manner typical of the film's flamboyance--Paco goes out of his way to rape Mick's girl and gets sent up.

There's a little interlude, evidently meant to portray Mick's rarely appreciated finer side, when Horowitz and Mick stage a prison break, allowing the hero a brief moment to console his battered sweetheart.

Paco finally arrives looking for trouble, but Mick, now inexplicably identified as a model prisoner, endeavors to avoid it, vainly of course.

All this movie has going for it is the occasional explosion of violence, and to the extent that the script has a purpose, it's designed to make arrangements for the ultimate no-holds-barred kiddo-a-kiddo between Mick and Paco, which is treated rather like a bullfight, with the other boys cheering the combatants on with cries of "Kill, kill, kill!" that reverberate like choruses of "Ole'!"

"Bad Boys" emerges as a textbook example of rotten melodrama. BAD BOYS, directed by Richard Rosenthal; written by Richard Di Lello; directors of photography, Bruce Surtees and Donald Thorin; production designer, J. Michael Riva; edited by Antony Gibbs; music by Bill Conti; produced by Robert Solo for Solofilm Company Presentations. This film is rated R. THE CAST Mick O'Brien .... Sean Penn Ramon Herrera .... Reni Santoni Gene Daniels .... Jim Moody Horowitz .... Eric Gurry Paco Moreno .... Esai Morales.