NEW YORK — "Sweet dreams" is an alien notion to Allison DuBois.

As viewers of the NBC drama "Medium" know, she rarely gets a night of undisturbed sleep. And when she wakes up with a gasp — another nightmarish warning of someone's death — she isn't alone.

"What's wrong?" husband Joe asks drowsily, as if this weren't a regular event.

But, apart from her psychic danger signals, Allison shares a normal family life with Joe, complete with hectic schedules, stretching the budget, and devotion to each other and their kids.

Viewers can relate. At least as much as Allison's otherworldly knack for cracking homicide cases, it's the DuBois' domesticity that accounts for the success of "Medium."

Allison has never gloried in what sets her apart from the rank and file.

"At the beginning, I wanted her to lack confidence and feel apologetic about having this ability," says series star Patricia Arquette. "Then, slowly progressing through the seasons, she's gained more assurance, and gotten more protective of her gift."

Meanwhile, Arquette has come to see the series as its own kind of gift since its premiere in January 2005.

Before that, she had been in numerous films including "Bringing Out the Dead," "Stigmata," "True Romance" and "Ed Wood."

Now 40, she was born into a show-biz clan. Her grandfather was comedian Cliff Arquette (better known in his persona of Charlie Weaver), her father was actor Lewis Arquette, and her siblings — Rosanna, Alexis, Richmond and David — became actors along with her.

But for Arquette, there's something special about "Medium" beyond the acting job.

"It's been a way for me to explore death," she says.

"I've had a lot of experience with death in my life," she goes on, with no trace of morbidness. "My mom and dad have both died. A lot of my friends died young.

"I've had so many feelings about death, and dwelled on how people I loved had died, and what their last thoughts were. Friends who had overdosed: Did they recognize they were about to die? My 12-year-old best friend who got hit by a car: The moment between getting hit and falling to the ground and dying, was she scared?

"Allison is a woman who doesn't understand why she is privy to the darkness of death, and to the depth of loss, and I felt like I was intimate with similar feelings, and didn't have a place to put them. So, in that way, I was very grateful to have this part."

Even so, she found the pace of a TV series (as well as playing the same character longer than a few weeks) to be a challenge after so many movies.

"It's an endurance test," Arquette says. "And there are times where you go a little bit crazy as an actor: 'Wait a minute, haven't we already shot this scene? Haven't we said similar things to each other on another episode?'

"Oh, but married people do that all the time!" she reasons. "They have the same conversations during their relationship. So I surrender to it and tell myself, 'Let me do what's true here, and not worry whether it's the same as we did it before."'

Jake Weber, who plays Joe, makes an ideal partner, she adds.

"There's something very genuine about his acting. When I'm in my character and he's in his character, I can always see why Allison loves him. I can see why they're together."

With a chuckle, she describes how she and Weber shoot a scene.

"I'm sort of a people-pleaser, and since I know with a TV series everybody's got to make their day, I try to do the best work I can in those circumstances, even if I feel like we're rushing. But Jake will go, 'Wait! Stop! Don't you feel like that was clunky right there?'

"And I'll go, 'Yeahhhh.' And he'll go, 'Well, let's talk about it.'

"He's taught me that, ultimately, it's good for everybody when you take the time to do it right. And that," she says, flashing a sheepish look, "has been a hard lesson to learn."