The notice outside the big gray double-doors was simple and to the point. SET CLOSED, ABSOLUTELY NO ADMITTANCE. You find notices like this outside a lot of film studios, and they tend to have a certain elasticity. This one, outside what looked like an aircraft hangar but was actually Stage D at Universal Studios, meant it.

Inside, Elvis Presley was filming. And where Elvis goes, the barriers go up as if some sinister germ warfare experiment were being carried on within. Like a suckling infant, he is swathed and coddled against the realities of the world outside, as if he were made of rare porcelain rather than hewn from good old-fashioned Tennessee stock.

But this day he was on show. I had been given the magic formula. The secret open-sesame known only by its brand name of "Colonel Parker's Okay" had been handed me. The doors swung wide, and I was in.

They say Colonel Parker is the man who built Elvis from the erotic gyrating days of the swiveling Pelvis through 14 long and fruitful summers to his present status, by pushing and pulling his protege through the tricky cross-currents of pop music taste. I wouldn't know. I had asked to see him, this onetime Texas fairground barker, to thank him for the green light. But he was always somewhere else. In his office at Universal, over at Metro, down in Palm Springs, in Las Vegas to lay the trail for the next live show...always somewhere else.

No matter. Who needed Colonel Parker when Elvis himself was alive and well and filming? The Publicity Man who escorted me as close as if he were handcuffed said proudly: "I'd like to work with him again, he's so sweet and uncomplicated. I was surprised you got through — no one's talked to him yet, you know. There must have been a good breeze blowing."

The good breeze continued to blow as far as the set. A mauve-walled pad with kitchen adjacent and a king-size bed visible through half-drawn yellow curtains. Elvis sat at a table, staring at his hands, while three mini-skirted girls, Mary Tyler Moore, Barbara McNair and Jane Elliott, scurried around with trays of food.

The film is about three nuns who pose as nurses to "identify with the people" in a Negro ghetto in New York. The title is Change of Habit (yes, it is) and stars Elvis as a medic who falls for one of the nuns.

Elvis is wearing a paint-stained blue denim shirt and tight blue jeans. He looks relaxed and affable and rather meatier around the jaw-line than one remembers from previous films. Marriage (back in May 1967 to Priscilla Beaulieu) is obviously agreeing with him.

His eyes have that smoky slow-burn of the old-time movie vamp. He siezes a guitar and strums a few chords. It's the last week of shooting, and like the good days between exams and the end of term.

The atmosphere on the set is hip and loose, full of leather-clad youth and clever in-talk. The director is thin and intense, wears a check shirt and gym shoes, and is called Billy Graham, which is going to look interesting on the posters of a swinging nun.