"Dig it, dig it , dig it, dig it, dig it, dig it, dig it, dig it, dig it, dig it, dig it."

- "Dig it." by The Beatles

There never has been anything remotely like The Rutles.There has, however, been something exactly like The Rutles: The Beatles. That's what makes the Rutles saga so fascinting, so funny, so sad, so funny again, so sad again, then rather funny, the quite sad, then sadly funny, then comically tragic and finally, utterly and malicioucly meaningless.

"All Your Need Is Cash," the Rutles story in 90 blood-curling, curd-curdling minuts on NBC (Channel 4) at 9:30 tonight is arguably and probably the most elaborate prank ever played on primetime television and an invaluable forge document of a phenomenon that never really happened.

Eric idle, the Monty Pythonite who write the script and plaus Rutle Dirk, is on the record as stating categortcally. "The Rutless story is a legend. A living legend. A legend that will have a lifetime, after lots of other living legends have died."

His scenario, which tells the alleged Ruthles story as allegedly as possible and the film's direction, by "Saturday Night Live" filmaker Gary Wels satirize not obly The Beatles and Beatlemania and the era they spanned and defined, but also the machinery that made it happen and in fact the machinery that makes all fads, rages, wonders and living legends of our time happen.

The gap between reality as we remember it and the film's parody version sometimes gets so narrow that the satirical edge is just barely visible. Even so, "Cash" never degerates to the imitative level of a Beatle look-alike contest or an Elvis clone.

"Cash" lampoons the audience as well as the show it is watching, so that by the time The Rutles get around to the seminal flop "Tragical History Tour," in the I-Am-The-Walrus phase ("piggy in the middle, do a Pooh Pooh," they sing, enigmatically), we get a rousing insight into just how dumb we were in the '60s, just how dumbs '60s were, and just how dumb a littles part of each of us will probably always be.

How dumb? The Rutles soundtrack album, a collection of Beatles parody songs by Neil Innes, has already sold 58,000 copies for Warner Bros. Records which has been printed up 120,000 of them. Billboard lists it as No. 153 with a bullet and Cash Box lists it as No. 126 with a buttler AND THE BLOODY SHOW HASN'T EVEN BEEN ON TV YET!

In New York, disc jockeys are playing Beatles songs and Ruthles songs side-by-side. Already there are rumors of the Rutles getting back together. And already there are denials. There is some question that they ever really got together in the first place. Onassis a Fan?

Jacqueline Onassis may become a Rutles fan before it's over, though no one knows for sure.

She does not appear in the program, but these people do: George Harrison, mick Jagger, Bianca Jagger, Paul Simon and ex-Pythonite Micheal Palin. Lorne Michaels producer of "Saturday Night Live," is executive producer of the special and he has a cameo role, as do "Saturday Night" stalwarts Danny Aykroyd, Bill Murray, Gilda Radner, and John Belushi as "Ron Decline, the most feared promoter in the world."

The part of Rutles press officer Eric Manchester is played by Derek Taylor who IN REAL LIFE WAS ACTUALLY IN FACT the Beatles' press agent for five years. Taylor, 45, now is in charge of creative services for Warner Bros. Records, which picked up the Rutles option when Arista Records dropped it with a thud.

"Eric kept saying 'Rutles Rutles Rutles.'" Taylor recalls in his Hollywood office, as plastic radio dispensing classics from a corner. "But the first I heard of it was from one of The Beatles - Beatle George - who said, 'There's this new band, The Rutles, and he showed me a videotape.'"

The tape marked the first public appearance of the "Prefab Four," on Idle's British TV show "Ruthland Weekend Television," a series Taylor is hard put to describe except to say, "Whatever 'existentialism' means, there was plenty of that."

Rutland was "the tiniest county in England," Idle explains by phone from and editiong booth in New York, and "in 1967, it was declared no longer a place. It became part of Leicestershire."

Taylor eventually got such a bad case of Rutle fever that he had thousands of promotional buttons and postcards printed up. "I'm looking for gold or platinum," he predicts of album sales; gold is 500,000 and platinum 1 million.

The prospect that some consumers will not quite realize all this is parody does not disturb Taylor in the least. "A lot of people, yes, are going to believe there was a Rutles," he says between sips of tea from a cup with the queen's picture on it. "What does that say? I may say that a lot of people are jolly decent.

"Or it may say they are very dumb."

Idle says his film is by not means a savage attack on The Beatles and say 'Rest in Peace,'" says Taylor. Of course he knows the rest will bot really be peaceful. There's "Bealtemania" on the stage, a forthcoming film of "Sgt. Pepper's Lonely Heart clun Band," a forthcoming Ringo Starr NBC special, and plenty of other forthcoming Beatleabilis.

Will any of The Beatles be offended by what they see in "All You Need Is Cash"? Not "Beatle George ," obviously, but of the other three, Taylor says, "Yes. I think they might not enjoy it all. Yes. But ir there is offense I think it will only be temporary because it's a loving look at something that for many years had life all its own way. Beatlemania can go on and on but they'll never get back together. This Rutles thing makes it clear; having seen this they'll see how daft it would be." Free Money

"All You Need Cash" was not produced for free. Money was involved: $500,000. Originally it was intended for the late-night youth audience that tunes in "Saturday Night" but when Idle and Weis (they are Productions) saw their own rough footage, they knew this was prime enough for prime time.

Only at NBC, of the three networks, could there be found a high-ranking executive with a funny bone hip enough to see what's funny about The Rutles. That chap is Paul L. Klein, NBC's chief programmer. Weis waited with Idle outside a screening room door while, inside, Klein watched a tape of the show. Weis had his ear to the door but couldn't hear any laughter. "I thought, 'aw-oh,'" Weis said later. "But it turns out Klein was sitting near the machine and that he laughs very low and he laughed a lot. I mean. 'Cellarful of Goys' - he's gotta fall on the floor, right?"

Weeks passed.

America matured.

Rutles pre-hype continued at an outdoor restaurant on Santa Monica Boulevard. It seemed the perfect place for a chat with Weis and producer Craig Kellem and a memner of the press. Unfortunately , every two minutes all conversation was oblitered by a medley of sirens from police cars and ambulances circling the block as if the SLA headquarters were in the restaurant kitchen.

"You know," said Weis between sirens, "on the 'Tragical History Tour' squence, one of the British cops on the wall waving his arms was in the original "Magical Mystery Tour' movie. He came up to me and said, 'Oh yes, I did this with those guys the last time.' I mean, he had no idea, he was so out of it again. 'Those guys.'"

And when The Rutles run down a fire escape in their first movie. "A Hard Day's Rut," it's the VERY SAME fire escape The Beatles ran down in their first movie, "A Hard Day's Night."

Suddenly the sound of sirens started to come closer again. "I'll tell you who the killer of JFK was!" shouted Weis. "It was - "

But the sirens drowned him out. Aspirin and Sucrets

Idle refuses to be drawn into speculations about deeper meanings of his film. Instead he just chortles, "It's obviously a spoof, isn't it? Ha ha ha ha ha . . . ."

This leaves a number of questions unanswered.

What does the film say about Out Time? "That it's now the '70s and will soon be the '80s," saus Idle.

What if the public demands more Rutles songs, there being no possiblity of more Beatles songs? "Oh well, Neil can come up with another album," says Taylor.

Is there any difference between the American and British versions of the show? Yes. One naughty word to be heard in Great Britain will not be heard here. Also, there leg mea be more reference to "inside leg measurements" in the English one because, says Taylor, "inside leg measurements always raise a laugh in England."

Will The Rutles ever get back together again? "I can only echo the words of Mick Jagger," Taylor says. "'I hope not.'"

What did he consume at that outdoor restaurant on Santa Monica Boulevard? Two vanilla milkshakes. Epilogue

"All You Need Cash" is funnier by far than a number of current movie comedies. including "The World's Greatest Lover," "High Anxiety," "Oh God" and "The One and Only." but more than that, it is a piquant comic epitaph to the rollicking, frockling '60s. -It's time to end the '60s," Idle says, but the ironic effect of "Cash" may ne to prolong them even further, perhaps so that they will last to the end of the '70s.

Then we'll be able to pretend the '70s never really existed and that Donny and Marie never actually had a weekly television show watched by million of people.

The Rutles sum it all up when they sing:

"Walky talky man says, hello hello hello with his, Ballerina boots you can tell, he's always on his toes. Hanging from a Christmas tree, creeping like bogery man, getting up my nose, hey diddle diddle, the cat and the fiddle, piggy in the middle."

Piggy in the middle, indeed.