Provocative gossip in a hip, slick wrapper, "The Last Days of Marilyn Monroe" may be on a certain level deplorable, but it is also on another -- lower -- level, irresistible. The 90-minute documentary, produced by of all people the BBC, airs at 8:30 tonight on Channel 5.

Anthony Summers, who wrote "Goddess: The Secret Lives of Marilyn Monroe," was the consultant for this program, the essence of which was to be contained in a report on ABC's "20/20" late last year -- until ABC News President Roone Arledge refused to let it on the air. Arledge's old Kennedy ties were blamed by some at the time for his abrupt decision; the broadcast assertssw,-2 sk,2 ld,10 that both John F. Kennedy and his brother Robert had affairs with Monroe in the early '60s.

When it's all over, "Last Days" has proved nothing and recycled an awful lot of malingering scandal. All that can reasonably be accepted is that there remain doubts about the precise circumstances of Monroe's death, and that she hobnobbed with the reigning glitzeritzi of her day. The notion that she was murdered, that the overdose of barbiturates that killed her was administered by someone else, is entertained but by no means proved. Why would Monroe have been murdered? Because, one interested party contends, she knew all about the CIA's alliance with the Mafia for the purpose of assassinating Fidel Castro. Ahem.

As there has grown up a subculture of conspirophiles where the assassination of President Kennedy is concerned, so there appears to be a thriving cult that insists there was more to Monroe's death than the suicide, or accidental overdose, of a brutally unhappy Hollywood star. "Marilyn Monroe was murdered; she did not commit suicide," says Jack Clemmons, the policeman who was at the Monroe home the night of her death, with great finality. But the narrator of the documentary says Clemmons' chief article of evidence, something to do with whether there were traces of barbiturates in Monroe's digestive system, is flimsy and unreliable.

However, there was clearly an appalling sloppiness in medical, or at least record-keeping, procedures following her death. Someone really ought to do a study called "Botched Autopsies of the '60s." If only the medical examinations of famous dead people had been more competently handled at the time, conspiracy theorists might not have quite so much ground for suspicion now.

Some of those trotted out here for testimony about Monroe and her Kennedy dalliances seem of dubious authority -- the daughter of her psychiatrist, for instance. One of Monroe's neighbors. Or former senator George Smathers, who says only he "had heard there was something that was going on" between Monroe and RFK. Former Los Angeles mayor Sam Yorty is another star witness, but what he repeats is also mostly hearsay. The owner of the ambulance firm that picked up Monroe's body and took it to a hospital insists she was still alive when the ambulance arrived, whereas Monroe's aged housekeeper says she was dead. And so on.

Simply by programming something so potentially lurid as "The Last Days of Marilyn Monroe," Channel 5 would seem to be reflecting the vulgar tabloid tastes of new Metromedia owner Rupert Murdoch. But the fact is, though the content may be sensationalistic, the program, written and directed by Christopher Ogliati, is a very handsomely produced package. The interlacing of film clips, interviews and a reenactment or two is masterfully done. If this is pandering, it's classy pandering to be sure. Maybe Arledge rejected it for being too tasteful.

Among those who insist that both Kennedy brothers were amorously linked to Monroe -- John Kennedy even after being elected president -- is Deborah Gould, ex-wife of Peter Lawford, at whose Malibu beach house much philandering is alleged to have occurred. Gould says of JFK and Monroe, "It was a sexual relationship for sure, but much deeper than that, if you know what I mean." Not exactly, no, and the interviewer doesn't pursue the distinction. Gould also says "Bobby got very infatuated" with Monroe later.

In what may be the program's lowest moment, a private detective who says he listened to tapes that resulted from the mob's bugging of the Lawford home (Jimmy Hoffa wanted dirt on the Kennedys) recalls hearing "the springs squeakin' " in a bedroom allegedy shared by Monroe and JFK. "Last Days" is the National Enquirer as it might have been put out by a proper Fleet Street journal -- foul-minded but actually rather dignified in presentation.

Does the program tarnish the Kennedy image still further? For those who want to remember the best and still believe in what was believed in then, the mud slung here is largely irrelevant, and the Kennedy figures being discussed might as well be the comic book creatures of a prime-time soap opera. However, after seeing again the film of President Kennedy's impossibly garish Madison Square Garden birthday party, with Monroe pantingly undulating her greetings, Ronald Reagan's show-biz connections, even his being seen in the company of Frank Sinatra, begin to seem almost wholesome. We can't kid ourselves that the Kennedy style was all Pablo Casals and Robert Frost, can we?

Tom Clay, a disc jockey who says Monroe contacted him for company after hearing his sentimental commentaries on the radio, recalls meeting her and finding that even at the height of her glamorous fame, she was lonely and bored. Not very originally perhaps, but very accurately according to most known accounts, he says that "she seemed like a little girl lost." It is a poignance that is clearly not lost on those who made "The Last Days of Marilyn Monroe"; indeed, it is a running theme that, however banal, keeps rescuing the thing from scurrilousness and lifting it out of the gutter.