STAGE : ‘Nick & Nora’ . . . Inside the Bunker : The revision-plagued Broadway musical based on Hammett’s sleuths opens tonight, but leading man Barry Bostwick says he isn’t sure what to expect: ‘It’s just been such a long, drawn-out process.’

On top of the living room coffee table in Barry Bostwick’s penthouse is a well-thumbed manual: “50 Places to Find Peace and Quiet in New York: A Guide to Urban Sanctuaries.”

“Isn’t that just the kind of book you’d expect a Californian to buy immediately after getting off the plane?” laughed the actor.

As the star of “Nick & Nora,” the new $5-million Broadway musical, Bostwick has been in need of those sanctuaries--and the hot tub he had installed on the roof shortly after he began leasing the apartment. Ever since previews of the show began in early October, he and his co-star, Joanna Gleason, along with the rest of the cast and production team, have been in the bunker amid reports that the musical was in trouble. Without the benefit of an out-of-town shakedown cruise, the show immediately came under heavy fire from Broadway mavens, for whom, as Cole Porter once said, “hating a show is almost as much fun as loving one.”

The doomsayers may have been premature. In the past, shows have been rescued at the 11th hour and Arthur Laurents, who directed and wrote “Nick & Nora,” may be able to lift this one off the shoals. But tonight’s opening comes after more than two months of frantic script and song changes, constant rehearsals, and dispiriting gossip.

In late October, just weeks before the show was initially scheduled to open Nov. 10, it was clear that Bostwick felt neither the production nor the cast was prepared to meet that deadline. Not surprisingly, a few days later, word came from the press office that the producers had decided to delay the opening for a month. At the time, the 46-year-old actor, drawn and beleaguered, sketched a portrait of what it was like to return to the theater amid such intense turmoil.

“It’s frustrating, it’s panicky, the mood swings are really great,” he said over an after-theater dinner at Puleo’s, a Broadway hangout. “I find the theater so anxiety-inducing. Why would I want to put myself through that kind of pain?”

Glory, ambition and money, for starters. But there’s also the thrill of creating something new for the stage. After all, Bostwick is no stranger to the high-pressured crucible of Broadway. Born in San Mateo, Calif., he moved to New York in 1967 shortly after graduating from San Diego’s United States International University School of Performing Arts. He earned a Tony nomination for the dramatic role of Joey in the 1976 production of “They Knew What They Wanted,” but it was in the musical theater that he scored most prominently, receiving another Tony nomination for his portrayal of Danny Zuko in “Grease,” and finally copping the theater’s top award in 1978 in the title role of “The Robber Bridegroom.”

Seduced away from theater by film (“The Rocky Horror Picture Show,” “Movie Movie”) and television (“War and Remembrance,” “A Woman of Substance,” “George Washington”), Bostwick hadn’t stretched his musical muscles since 1981 (in the Los Angeles production of “Pirates of Penzance”) when the chance to do Nick Charles came along. The adventure started in earnest when he flew out to New York to meet Laurents and Gleason on the opening night of the director’s Broadway revival of “Gypsy,” starring Tyne Daly, in November, 1990.

“That night, I met Joanna and fell in love with her,” Bostwick recalled, who had seen her Tony Award-winning performance in “Into the Woods.” “We both felt it was the right time in our careers to play these characters. This was an ambitious, sophisticated, romantic musical comedy. When was the last time that was tried on Broadway?”

The show is based on Dashiell Hammett’s legendary sleuths, Nick and Nora Charles, first incarnated in a series of novels called “The Thin Man” (which happened to be the shape of the victim in the first novel). The soigne, martini-sipping couple solved their murders amid much witty banter mingled with yaps from Asta, their wire-haired terrier. The popular success of the novels spawned an equally popular series of films in the ‘30s and ‘40s, starring Myrna Loy and William Powell, and in the late ‘50s, Nick and Nora had yet another reincarnation in a television series, featuring Phyllis Kirk and Peter Lawford.

Bostwick said that Laurents, who is also writing the book of “Nick & Nora,” based his characters on the original novel that emphasized the Greek immigrant roots of Nick Charolopoulis who marries a San Francisco socialite and in the process acquires not only millions but also a new name. In the musical, class tensions underlie the murder mystery plot, which offers plenty of opportunities for opulent sets and costumes, romantic songs and sparkling repartee--and a morass of pitfalls when it all doesn’t hold together.

After the first previews of “Nick & Nora,” the Marquis Theatre’s backstage wasn’t a happy place to be, said Bostwick, but he handled the crises in as controlled a manner as possible. “When people are bouncing off of walls, my fear makes me very calm. I know some people like to create out of confusion but I like to create out of serenity. You saw my dressing room.”

Indeed, it was spare and uncluttered, almost zen-like--what you might expect from someone who meditates daily and makes Japanese pottery in his spare time. (He brought along his wheel from his Beverly Hills house.)

He likely needed this serenity while thinking about how to suggest--even insist on--changes from his collaborators, who are legendary Broadway talents. The songs are by Charles Strouse (“Annie”) and Richard Maltby Jr. (“Miss Saigon”), and Laurents, who directed “La Cage aux Folles,” also has written the books for such landmark musicals as “West Side Story” and “Gypsy.” The director who has a reputation for brutal, if not cruel, frankness isn’t exactly someone to whom you can go up and say, as Bostwick put it: “Now, write me a funny line, dammit!”

“It’s been a slow, hard, grinding process,” he said. “Sometimes Arthur feels the best way to direct is to tell you that everything’s terrible, that you’ve failed. Finally, I told him, ‘I don’t work well that way. Don’t tell me that I’ve lost it all, that I’m ruining the show and that if the critics had been here last night, I’d be back on the street. If you give me specifics, I can work on them and then we can create something together.’ ”

From his bag, Bostwick pulled out a legal note pad and a dogeared script heavily marked with notes to himself. On the pad, he added some comments to a growing list that he planned to discuss with Laurents. “It’s important to know when to speak up and when to keep quiet,” he said. “I’ve been patient. But starting next week, I’m going to put some pressure on him.”

Six weeks later, 10 days before the Dec. 8 opening, Bostwick sat on the living room couch of his apartment, surrounded by pages of yet more revisions to go into the show that night. Since late October, he said, three new songs had been put into the show, scenes had been thrown out wholesale and new ones inserted. Though still in the middle of the war, he appeared noticeably more relaxed.

“I’ve put my two cents in,” he said with some resignation. “I had my meetings with Arthur, I’ve written my letters, I’ve argued all I can. Now it’s a matter of acceptance and making the most of what I have--which is considerable. My ego’s not involved in thinking that I can really change this thing. I’m an employee. It’s Arthur Laurents’ circus. He’s the puppeteer and I’m just one of the puppets.”

Bostwick said that at a recent rehearsal, Laurents announced to the company that the show had “turned around.” Audience response was up, the cast’s commitment to the material had improved, and even word on the street was kinder. Though the actor said he hopes that’s true, he still sounded skeptical. “I’m too close to the show to be objective,” he said. “It’s just been such a long, drawn-out process.” Still, there are some good signs. People are no longer deserting the show after the first act and he’s getting more visitors backstage . . . “whereas, three weeks ago,” he said, “I was just a lonely boy, lonely and blue.” And, he added, the applause at the end does sound genuinely enthusiastic, even if the loudest ovation is still reserved for Asta, the dog.

In fact, Asta and Nick now have more scenes together and Bostwick is enjoying them despite W. C. Fields’ classic dictum about never acting with children or dogs. At one performance, when Asta was feeling under the weather, he had to go on with the understudy, who hadn’t yet learned any of the tricks. He kept a firm grip on the animal, physically moving it through its paces. (“It was like working with an animated prop.”) Bostwick said he even began bringing Asta home with him on some nights for a little male bonding. “Actually, I figured I was the only person in the cast who wasn’t sleeping with a co-star and I should rectify that,” he cracked.

The joke is a sly reference to a gossip item that told of a romance between Gleason and Chris Sarandon, who plays a slick con man in the show. Alex Witchel suggested in her New York Times theater column that the affair was making Bostwick’s onstage chemistry with his co-star appear anemic by comparison. The day after the story appeared, said the actor, the mood of the company was tense and Laurents was furious that someone in the cast may have been talking out of school. The company moved their wagons into a tighter circle.

“Our job is tough enough without having to put up with this stuff,” Bostwick said. “It’s totally off the mark, but some people in the theater love to hear it, to create it, to fight against it. I reject it. I come to my little rooftop here and I wait for the sunset. My life is about other things.”

Indeed, the bruising ride of the last three months has served to reinforce an emotional shift in the actor’s personal life, which he said began a couple of years ago. He professed he is no longer as single-minded about his career as he once was. “The work has become a way to support my life,” he said, “but hopefully a more meaningful life than I had in the ‘60s, ‘70s and ‘80s when my career was everything. It’s not everything now.”

Bostwick is now more preoccupied with spiritual concerns. He serves on the board of AmFAR and considers AIDS research a priority (“We have to get through it, not only physically, but also emotionally and spiritually”). Indicative of another priority is his copy of Sam Keen’s book, “Fire in the Belly: On Being a Man.” Bostwick, who was married briefly and recently went through an amicable divorce, said that for the last couple of years he’s been exploring relationships with men in “non-competitive atmospheres.”

“As a straight male,” he said, “I’ve spent the last 44 years of my life avoiding men because of my own relationship with my father, or whatever, and I’ve suddenly awakened to discover that I’ve neglected more than half of the population out of an unwillingness to open myself up. So I’ve recently spent a lot of time in male groups. The options in my life have so widened that I have no idea what my next relationship is going to look like.”

Both writing and pottery-making, he said, have helped him regain some control over a professional life that recently has come to resemble something of a crap shoot.

Win or lose, Bostwick said that he sees acting more and more like a game. “It’s fun,” he said, “but it no longer defines who I am. That’s the reason I’m attracted to Nick. He’s a man who doesn’t need approval from others. He’s a loner in the old style.”

Asked if he’s yet started having fun playing Nick, the actor took a deep breath, fixed a pair of steely blue eyes on his guest, and sighed: “Ask me that question on December 9th. If I discover that I’ve wasted a year of my life, that the show doesn’t end up as something I’ll enjoy doing, then I’m not going to be a happy camper. But the theater is a dangerous way of working, full of great risks and compromises and rewards. There are no guarantees. And who knows? It just might work.”