BEVERLY HILLS — A sign over the doorbell of Jack Nicholson's home asks visitors: Please, don't ring before 10 a.m.

Nicholson is a bit sheepish about the reason.

"It ain't 'cause I'm partying every night, I'll tell you that," he says, padding down the stairs of his split-level ranch house as he tucks a blue Izod polo shirt into his khakis. "It just seems like a good time of day. And, to be honest, I need the sleep. I'm getting into my later years."

Jack Nicholson is not who you think. Sometimes, Nicholson says, he's not who he thinks.

"I don't mind the wild stories about my personal life," says Nicholson, 69, settling into a living room chair with the first of many cigarettes. "Nowadays, they're a good distance from the truth. I'll play along, because it's a good story. Even I believe it sometimes. But I'm slowing down."

Yes, Nicholson remains, along with Hugh Hefner, Hollywood's most notorious bachelor. He is still fond of having a starlet on his arm at a premiere — and occasionally bringing her to his "pad." He still adores swearing and cigarettes and beer.

But Nicholson can be surprisingly domestic. He lives in the first home he ever bought, a four-bedroom rambler he got with the dough he made from 1969's Easy Rider. He struggles with parenting, particularly with not sounding like a hypocrite when he lectures his teenage children about avoiding alcohol, drugs and random sex — the ingredients of Nicholson's youth. He likes pudding for breakfast.

And despite the swinging-single reputation, he can be, well, a homebody. He's in more evenings than he's out, usually by 8 if the Los Angeles Lakers aren't playing. When he doesn't have his nose in a thriller or a book by Maureen Dowd, he's watching the shows he TiVos religiously: CSI, Without a Trace and Monk.

"People would be astounded by how much I stay here," he says, looking out on a backyard that once bordered that of his idol, Marlon Brando. (He bought the late actor's property.) "At my age, you begin to enjoy the solitude, the quiet. That's OK if people think different. I love to keep them guessing, to see the surprise on their faces."

People also may be surprised by his latest turn as a gang boss in The Departed, which opens today. Nicholson unnerved Warner Bros. executives with his insistence on wholesale changes to his character, mainly that he have more guns, cocaine and sex. Lots more sex. "I wanted him to be more corrupt than anything I'd seen on TV," he says. "I needed this to be different."

Perhaps that's because the film embodies something personal for him. It's his first movie in three years and the first he has done with Martin Scorsese, a friend of three decades. It's his first serious part since 9/11, when he decided he would do only comedies for a while.

Most important, it's an opportunity for Nicholson to show that he still has the chops for the rebel roles he cherishes. He doesn't plan to let age or health problems slow him. Though he had surgery Tuesday to remove a stone in a salivary gland, Nicholson is to begin work this month on The Bucket List, a drama with Morgan Freeman about two terminally ill men who flee the hospital for a final road trip.

"Hollywood isn't all that interested in the dramas of middle life and old age," he says. "And I understand that. Young people drive the medium."

He sits up in his chair and leans through the smoke, and suddenly he's the Jack from the movies. The one with the impish grin, coin-slot eyes and gravel rasp. The one who has won more Oscar trophies and nominations than any living actor.

"But I'm still alive and kicking," he says. "I can still cause trouble."

The 'lay down' script

Trouble has treated John Joseph Nicholson well. He realized that it would when he was 32 and sitting in a theater at the Cannes Film Festival, watching Easy Rider with a packed house.

Suddenly, he was rebel chic. He had worked for 11 years on film crews and producing and acting in Roger Corman horror flicks such as The Raven and The Terror.

By the time he got back to Los Angeles from Cannes, "the offers were coming," Nicholson says. "I thought I was going to be a director or producer, and suddenly everything changed."

What hasn't changed, Nicholson says, is his hunger for scripts that allow him to shake up his public persona. He says there aren't many. Over the past decade, he has done only about a movie a year. He gives few interviews, and none to television media.

"The more that people know about you, the quicker they'll be bored with you," he says. "Hell, you'll get bored with you."

But he still jumps for what he calls "lay down" scripts, screenplays that read like a winning poker hand. "All you do is lay it down," he says. "Any moron could play the part, and the movie would still be great." He counts among them Easy Rider, One Flew Over the Cuckoo's Nest, Terms of Endearment and Something's Gotta Give. He claims that when he read the script to Endearment, he knew he'd win the best-supporting-actor Oscar for it. He did.

The Departed, he says, wasn't a lay-down script. He initially turned down the role of Irish Mob boss Frank Costello — brought to him by friend Leonardo DiCaprio — because it felt more like a cameo.

"The character seemed a little regular," he says. "And I don't want to play a regular anything."

Nicholson has turned down many parts he felt were too regular, stereotypical or commercial. He declined the role of Michael Corleone in The Godfather and the Robert Redford role in The Sting, instead playing Billy "Bad Ass" Buddusky in The Last Detail.

"It's not easy in this business, but you still have to treat it as art," he says. "You know that little voice in the back of your head? The one you don't want to listen to? That's your integrity."

Still, he wanted to work with Scorsese, a man he'd gotten to know from visiting the sets of Mean Streets and Goodfellas to see pals Robert De Niro and Harvey Keitel.

"We kept saying we needed to do something together, so I figured I'd suggest a few changes," Nicholson says. "I told myself I'd do the movie if Martin could handle the things I hurled his way."

Like a strap-on phallus.

Nicholson made the tabloids and gossip blog sites when reports leaked that Nicholson wanted his character to wear an artificial member, hold orgies and frequent porn theaters.

He still doesn't understand the fuss, and he says he would have pushed it further. "But Martin knows what he's doing."

Departed producer Graham King knew he was in for a long day when he visited the set and found Nicholson and Scorsese scheming together in a trailer. "I'm the one who had to go to the studio every day and report back. I'm the one who had to say, 'Yeah, shooting is really going well. Oh, and Jack wants to wear a strap-on.' "

Nicholson figured his decision to wear a New York Yankees cap would cause a bigger stir, because the movie was set and shot in Boston. "Sometimes," he says, "you've just got to see how far you can push people." That includes co-stars. The movie, starring DiCaprio and Matt Damon as two cadets who infiltrate the Mob and state police, required that both actors have a sense of panic throughout the film.

Nicholson decided to make sure DiCaprio was on edge. He asked a prop man to bring him a pistol to secretly pull on his co-star. Though startled by the improvisation, in which Nicholson accidentally drops the weapon and angrily fumbles for it, Scorsese kept the scene.

"On set, he is that character in a way," Scorsese says. "He doesn't come out of that, which is really good, because it keeps us focused."

And braced for the unexpected. In another scene, Nicholson planned to startle DiCaprio by setting a table on fire with bourbon and a lighter — until he found out his glass was filled with Diet Coke.

"When he signed on to do this movie, we knew he'd have to completely make this character his own," DiCaprio says. "It's written one way, and ... he's going to do whatever the hell he wants — and rightfully so."

Few people have earned the right to push boundaries like Nicholson. He has won three Oscars (for Endearment, Cuckoo's Nest and As Good as It Gets) and been nominated for nine others. Laurence Olivier has 10 acting nods. Among actors, only Meryl Streep has more nominations with 13.

"He's at the top of the pantheon," film critic and historian Leonard Maltin says. "He approaches each role with a passion that few people can. And at this stage in his career, he's willing to take risks others wouldn't. Look at Anger Management. He's willing to do a silly comedy with Adam Sandler. It wasn't a great movie, but he's not afraid to give it a go. He's still daring. He's the king of cool."

Nicholson shrugs off the praise. If anything, he says, he's trying to be less of an icon and is increasingly avoiding the spotlight.

"The Rolling Stones and I go way back," says Nicholson, who is a godfather to one of Mick Jagger's sons. "Now, there was a time when I'd go into an arena and whip that crowd into a living frenzy before they ever came on stage. But I don't do that anymore. I'm more likely to just see the show."

One of his proudest Oscar moments came in 2000 when he avoided the red carpet and slipped in a back entrance, and he claims that there isn't one still photograph of him at the ceremony. "One of the nicknames I'm silently happiest about is 'The Dodger,' because I've learned how to slip away from the party and the photographers," he says. "I'm not as willing to be that glazed guy walking the red carpet. I'm learning that as you simplify, whether it's your life or your acting, you get better. And I still want to get better."

Take fatherhood, for instance. Nicholson says he vowed to be a blunt parent after discovering, at 37, that the woman he believed to be his mother was his grandmother and the women he thought were his sisters were his mother, June, and aunt, Lorraine.

Not one to 'outsmart' teenagers

Nicholson acknowledges four children, including Lorraine, 16, and Raymond, 14, by Rebecca Broussard. (The others are Jennifer, 43, by ex-wife Sandra Knight, and Caleb, 36, by actress Susan Anspach.)

"I know I'm not going to become the first parent to outsmart a teenager," he says. "God knows I'm not a moralizer. All I do is tell them, 'Everything they say is bad for you is bad for you.' And I speak from some experience."

If there's one habit he says he can't kick, it's women. Nicholson hasn't married since his divorce from Knight in 1968 and has kept paparazzi scrambling with a multitude of beauties, including Angelica Huston and Lara Flynn Boyle.

He says he's "playing the field a little now, though not nearly as much as people like to think."

In fact, "I do get rejected," he says with a grin. "I still owe Nicole Kidman an apology. I didn't know she was engaged — or that she was standing with her fiancée."

He stands, stretches and puts out the last cigarette of the afternoon, chuckling at the memory of the ribald moment with Kidman and then-fiancée Keith Urban backstage at last year's Oscars.

He refuses to divulge the comment, though he seems to relish the gasp it drew from Kidman.

"Let's just say I'm getting older," he says. "But I haven't lost my sense of whimsy."