NEW YORK — "Californication" is replete with sexed-up, misbehaving characters who act first and think later (like the morning after, through a pounding hangover). This Showtime comedy boasts a fast crowd of consenting adults — in particular, David Duchovny as womanizing, self-destructive writer Hank Moody.

But the central figure on "Californication" is 14-year-old Becca, Hank's mostly levelheaded daughter who does what she can to take care of her dad while learning to accept him as he is.

She doesn't log a lot of screen time. No wonder: "Californication" is a raw, outrageous, bitterly funny comedy — and emphatically grown-up.

But in young Madeleine Martin's hands, Becca is conspicuous as the show's one true adult. She is a rarity among the characters, prepared to take command of her impulses. In a shabby-chic world of acceptable debauchery, she is the willing abstainer.

Not that she's a pill: She claims to worship Satan, loves "Guitar Hero," and has a flair for wry comments delivered with a poker face.

As the second season begins (7 p.m. tomorrow) Becca's first line is directed to her father right after he gets a vasectomy.

"How's the package?" she asks with mock concern.

Turns out, that scene will be just about all the actress who plays Becca gets to see.

"My mom TiVos the show," says Madeleine with an appreciative laugh, "and if I want to see my stuff, we fast-forward to it. My friends don't watch it, either. I think they saw a commercial once, and I guess it was inappropriate. They called me up and said, 'Oh, my goddddd!"'

Becca is typically glum, sad or introspective; the cloud seldom lifts.

Madeleine seems anything but. She's a pixyish 5-feet-1, with a china-doll face most often lit with a smile. During a lunch interview, she sparkles with plenty to talk about and giggle at, including an impressive list of stage and TV credits despite her tender age (she's almost 16).

This season on "Californication," Becca will deal with new things that upset her.

"I cry a lot," Madeleine reports. "I had a scene where I'm crying with Natascha (McElhone, who plays Becca's mother and Hank's ex). We did about 30 takes. They wanted to get all these different angles. I managed to cry on every take."

What's her trick?

"I used to think about my dog being sick," she explains, "but that's getting a little worn out — not that I don't care about my dog anymore. Now I listen to my iPod: I listen to the soundtrack of 'Donnie Darko' before every take. That helps."

When she auditioned with Duchovny for "Californication," Madeleine had never seen "The X-Files," the series that made him a star (though her two older brothers "were huge fans, so they were really excited").

Madeleine thinks acting's fun.

"Everyone says 'Aren't you disturbed' " playing tormented characters?

Not always. She did the voice of JoJo on the lighthearted kids' show "JoJo's Circus." But she also played the title role — a severely brain-damaged girl — in the Broadway revival of "A Day in the Death of Joe Egg."

"I'm not a method actor," she says, "so I don't have to BECOME the character. I know it's not real. I sympathize with the characters, to see why they are the way they are. With Becca, she's lonely and wants to have a dad who's like a dad, instead of like a child.

"She's fun to play," says Madeleine Martin with a smile. "Very grown-up for her age."