A nurse bends over the infant Mohammed Al Fay, who has just let out a lusty bellow, and delivers a classic Harold Robbins line:

"No need to cry any longer," she says. "Your mother and father are being married right now."

It is the climactic point (one of many) in "The Pirate", a four-hour mini series which will begin at 9 tonight on WDVM-TV, Channel 9.

Harold Robbins is the Burger King of American letters; pick up one of his novels and just like a whopper, you know exactly what you are going to get: power, lust, money lavish decadence and awful family secrets - with, of course, a bit of tasteful violence thrown in.

Robbins is almost unique among novelists in the ease with which he translates to the television screen, and to add to the attraction this time his 1974 novel has taken on an ex post facto timeliness. At a time when sheikophobia (fear of rich Arabs) has become nearly a national panic (will they buy the Washington Monument and install a muezzion in it?), here it is is with an epic about the tribulations of a rich Arab who turns out to be basically a nice guy, though a bit rough-hewn. (Perhaps part of the reason is that his particular Arab was actually a Jewish baby substituted for a stillborn Arab baby in the middle of a sandstorm - but enough of that.)

For three years, handsome, blue-eyed Arab entrepreneur and potentate Baydr Al Fay (Franco Nero) pursues blond California bombshell Jordana Mason (Anne Archer), and having sampled what she has to offer in Acapulco, Berlin, Paris, Stockholm - every major city except Beirut, where he has a wife - he has tried to make her wife No. 2.

His efforts are thwarted by her utlimatum: "I love you Baydr, and I want to be your wife - your only wife. Don't you understand that? That's the way I was brought up - only one wife at a time."

Baydr is reluctant to divorce wife No. 1, whose only shortcoming is that she doesn't produce anything but female offspring, and he needs a son to inherit an uncle's throne. Jordan's narrowmindedness is hard to understand, particularly after the big scene in which she tells her weeping mother to bug off and not make a fuss over her intercontinental affair with Baydr.

It is an idyll with only a few cloudy moments. They meet at the Kennedy inaugural ball (Baydr gives $100,000 to each candidate so he will be sure to get a ticket no matter who is the host), and he charms her with his quick repartee after she complains about the cold:

Bayd: "We can leave for Acapulco tonight. It's very warm there . . . "

Jordana: "Is there a plane leaving this late?"

Baydr: My plane leaves when I want it to."

It's love, or something, at first sight, but it takes Jordan years to win Baydr by playing her trump card - producing the male heir who will not be his until he terminates marriage No. 1. There is a great indignation scene and a threat of revenge from first wife Maryann (Carol Bagdarsarian): "To be left for an American whore with blond hair who has given him a bastard son!" and by the end of tonight's first installment, you just know that destiny is preparing a dooom as terrible as "Oedipus Rex" or "The Edge of Night."

The retribution will actually come in Wednesday night's installment, when Leila (Olivia Hussey), an alienated daughter from Baydr's first marriage, becomes a Palestinian guerrilla and engineers the kidnaping of little Prince Mohammed by a very mean bunch. By the time the plot is resolved, the viewer will have run the gamut of human experience, from having a baby in a standstorm to watersking on the Riviera.

And that's not all. There are some scenes in a Palestinian guerrilla training camp, a seduction involving a fading Hollywood actor who keeps a videotape camera over his bed, a substantial quota of blackmail and chicanery, bits of war action - notably the spectular burning of a grounded 707 to provide light for a helicopter landing - and a few scenes of rather hard-bitten romance.

There is at least one superior acting job - Eli Wallach as Ben Ezra, the secret father of Baydr - and a number of the personnel, male and female, are occassionally quite pretty. In spite of all this, one ends the four hours vaguely dissatisfied - partly from the limp dialogue, but even more from the feeling that the chief characters don't really deserve a happy ending.

THe color photography is excellent, but does not disguise the fact that the show is written in black-and-white.