When someone has just appeared naked in a $10-million movie, what's left to conceal?

Plenty, if the someone is Richard Gere, the multilingual, Mercedes-driving L.A. prostitute of "American Gigolo," who likes to fend off questions by saying, "My work is up there to see."

"What makes Richard different," says Paul Shrader, the writer/director of "American Gigolo," is that he has the traditional matinee-idol good look and yet he comes from the New York acting tradition, which does not place great stress on his external appearance. He can swing both ways. He can efface himself and be an actor or he can play his natural appeal."

"Gigolo," wherever else it may fall, falls loosely into the old Hollywood tradition of the "woman's picture" -- reoriented, of course, for today's woman. And today's woman has been making not secret of her keen, basic interest in Richard Gere.

At Shrader's behest, Gere made a semi-organized study of Alain Delon and his band of continental chic to prepare for his role in "Gigolo." "We don't have anybody like that in this country," Shrader had pointed out. But these days, in New York, the Gere-on-the-street could hardly look less like Delon, less like the sensuous Julian Kaye of "Gigolo" -- or indeed less like any of his movie characters, from the Italian-American singles-bar cruiser in "Looking for Mr. Goodbar" to the migrant farm laborer in "Days of Heaven."

Dressed in an army surplus jacket, shorn of a good 90 percent of his wavy hair, sapped of his southern California tan, Gere, 29, aptly compares his appearance to that of a "lobotomy victim." All this is for his role as a '30s Berlin homosexual in the Broadway play "Bent."

Eight times a week, Gere sweats through a part that includes a scene of noncontact, verbal lovemaking between two concentration cam inmates, building to a simulated sexual climax -- a scene that has helped draw numbers of gays to the New Apollo Theater on West 43rd Street. They, too, seem to regard Gere (and the play) with favor.

Has any star ever managed to train his sex appeal over such a wide expanse of territory simultaneously? Or to present such a vivid capsule demonstration of versatility?

And was that the idea? Was that what Gere himself had in mind?

Answers to these and other such questions will, for the most part, not be had from Richard Gere himself -- "a fiercely private actor" who "doesn't like talking about his work and . . . won't talk about his private life," to quote Paramount Pictures' own desperate biography.

Gere will say this: "The characters I play are all me -- as much as the man who's sitting before you now." In fact, he has said it, or variations thereon, about three times during the last half hour of a mass interview at New York's Essex House hotel.

A San Francisco reporter wants to know which of Gere's movie roles -- the stud in "Goodbar," the naive Bronx youth in "Bloodbrothers," the laborer in "Days of Heaven," the earnest GI in "Yanks" or Julian Kaye -- he likes the best.

"I like them all equally," says Gere. "They're like my children. They're all me." His answers are not always on quite this same level of lack of interest, but Gere would clearly rather be somewhere else -- perhaps at his dentist's, undergoing a little root-canal work.

The assembled press is asking questions like why he agreed to do the nude scene in "Gigolo"; whether a male prostitute with a vast Italian wardrobe and a rudimentary command of five Indo-European languages is a realistic character; did he get to keep that closetful of elegant clothes, and did he mind accepting a hand-me-down role from John Travolta?

Gere's answers, punctuated with many a long silence and a bewildered look, are:

As to nudity, "It was never any question. We were shooting. Certainly the guy that I was playing would not cover himself up when he gets out of bed. I'll do anything in the context of work."

As to veracity, the movie's hero may be an extradordinary character" but "this person exists who has a wonderful apartment, who knows art. . . . There are so many. These are outlaws who are on the edges of power." On the other hand, "clearly art is metaphor and [prostitution] is just a metaphor."

As to keeping the clothes, "I'm not allowed to say," says Gere mysteriously.

As to Travolta, Gere merely notes that he had the part first. He does not retrace the unpleasant chain of events whereby the part was taken away from him, handed to the hotter star and then offered back -- with about 10 days of preproduction notice -- after Travolta bolted.

But there was a recent period in Gere's career when he was not getting the parts he wanted and felt hopeless to do anything about it. "You know," he told Michael Segell of Rolling Stone a year ago, "after 'Goodbar' I had enough offers to play Italian crazies for the next 15 years. The bastards want to put you in a box with a label on it and crush it. If you have any hope of growing, of being taken seriously, you have to control the vultures.

"This business is a roller-coaster ride . . . When you hit the valleys, the hustlers and vampires like to probe the kinks way down at the bottom. But as soon as you make a buck, they show up again, friendly as can be."

In the same interview, Gere pointed to a poster of Alain Delon mounted for temporary inspiration on his living room wall, and said, "There was a time when I tried to pick up on his pouty narcissism. Look at his face. Don't you just want to slap him silly?"

Gere is one of five children of an upstate New York farmer-turned-insurance-man. Growing up in the Syracuse area, he was serious about music and gymnastics before he ever thought of acting. But at the University of Massachusetts, where he enrolled in 1967 and majored in philosophy, he began acting in plays and after two years left school altogether to join the Provincetown Players on Cape Cod.Later he worked with the Seattle Rep, was part of an abortive [WORDS ILLEGIBLE] group/commune in Vermont, and then went to New York's Greenwich Village, where he still has an apartment.

Producers and agents were interested in him from the start, and he quickly came up with his first role -- in a rock opera called "Soon." Later he played Danny Zuko in the New York and London productions of "Grease," and he appeared off-Broadway in San Shepard's "Killer's Head," a one-man play that had him strapped to an electric chair throughout.

Ever since his college days, Gere has been a movie buff, with a special inclination toward European directors. He hopes to work for Werner Herzog and Rainer Fassbinder -- not the typical highest ambition of American film stars.

"I like the Germans a lot," he says. "I think they're evolving something really special. There's an edge of inspired madness in their work." The directors for whom he has already acted -- Richard Brooks, Robert Mulligan, John Schlesinger, Terrence Malick and Paul Shrader -- are obviously not a random group, either.

With his photogenic looks and that distinctive assortment of movie credits, Gere has joined -- or stands ready to join -- the small circle of "bankable" young male movie stars, along with De Niro, Pacino, Travolta and Nolte.

He's the one with the silent vowel at the end of his name. But once you've said that, what else do you say?

If you're Gere's agent, Ed Limato, you say: "He's a wonderful client. He's not demanding, not anywhere near as demanding as other stars . . . He's never had another agent. He's been with me for at least eight years. We believe in each other."

You also say: "He constantly tells me that what he'd really like to do is go off to Europe and do four to six low-budget pictures for European directors. He's always threatening to run off to Bali or to some Tibetan monastery. He's very serious about Oriental philosophy. He makes me nervous."

If you're Rachel Roberts, the actress, you say: "I'm a great, avid admirer of Richard's work. I think he's on a par with another favorite of mine, Albert Finney." Gere and Roberts first worked together in 1975 in Alan Bennett's comedy "Habeas Corpus," with him as a country salesman peddling padded brassieres and her as an unusually well-endowed women he mistook for a customer.

"I said to him, 'You really are going to be a marvelous actor -- there's going to come a time when I'm supporting you in a film and you'll be the star,'" says Roberts. And her words proved prescient when Roberts appeared in "Yanks" last year as an English shopkeeper who opposes Gere's romane with her daughter, played by Lisa Eichorn.

David Dukes, Gere's costar in "Bent," says: "If I were to subtitle him, 'worker' would be the subtitle. When you work with stars, you always come in with trepidations. You always wonder how star-conscious they'll be. Richard's not that way at all." On the other hand, says Dukes, one day when they were eyeing a group of idle stagehands and Dukes commented that "they're probably earning twice as much as we are," Gere grinned and replied, "Not anymore they're not!"

With friends and co-workers, Gere is given to a fairly normal ration of small talk and jokes, says Dukes. Rehearsing their second-act love scene, for instance, "every now and then we'd try to talk about it and it all got kind of giggly and silly."

"Bent" begins with a campy, drawing-room comedy scene designed to lower the audience's guard. "The play is structured in such a way that you're taken in by it," says Gere. But he stresses that the picture of gay life in the Germany of 1934 is accurate as well as theatrically effective. "If you read any of Christopher Isherwood's books, you'll see that it's not that different a period from now. They're just people. You were not totally ostracized, being gay."

Gere did more than read Isherwood. For research, "I went to Dachau and I bought all the literature there and I read it and it's true," he says. Gay concentration-camp inmates wore pink triangles. Jews wore yellow stars. "In the camps, it was just a social phenomenon that the gays were at the bottom of the heap.

"What has been satisfying to me as far as the audiences go," he says, "is that there are so many people who have walked in to see this play who have no idea of what they're walking into. And the way the play is structured, they're brought into a gay life style and by the end of the play they relate to them not as gays but just as human beings, suffering."

But the "Bent" cast is almost entirely straight. "That dawned on us many weeks into rehearsal." Gere says an actor's sexual orientation isn't a factor in his ability to play the material: "I don't think art is created that way."

He sees "American Gigolo" and "Bent" as essentially similar thematically: Both have something to do with an inability to receive love.

"Gigolo" comes on like a whodunit, like a Hitchcock movie, but it's not that, according to Gere. "It's Paul's vision, his point of view." Gere especially likes the ending, which has him reaching toward Lauren Hutton through the glass barrier of a jail's visiting room. "Maybe in not fulfilling the expectations of a whodunit and hitting an audience with that type of ending, it's more illuminating," he says, adding:

"It certainly doesn't tie things up in an easy way."

Nor does Gere. But as he points out, his work is up there to see.