Mary-Louise Parker, <EM>Weeds</EM> Mary-Louise Parker, Weeds

It's enough to drive you to drugs. At the climax of the first-season finale, Weeds' pot-peddling widow, Nancy Botwin, was being seduced by a sexy new flame, Peter Scottson who turned out to be a DEA agent. But with the Showtime series' sophomore season now underway (Mondays at 10 pm/ET), the rebellious PTA mom, played by Mary-Louise Parker, won't let that get in the way of doing whatever it takes to support her family.

"Their relationship starts to take some weird turns," says Parker, who won a Golden Globe for her role. "The producers don't necessarily tell us where we're going, but his character turns pretty dark."

That's business as usual in this black comedy set in Agrestic, a deceptively placid California suburb. Things don't get any lighter inside Nancy's own home, where she and her family are still dealing with the loss of her husband, who died of a heart attack. This season her oldest son, Silas (Hunter Parrish), will become dangerously obsessed with his girlfriend, and her puberty-stricken son Shane (Alexander Gould) will fall under the questionable guidance of Nancy's no-goodnik brother-in-law, Andy (Justin Kirk), who talks his way into rabbinical school to avoid being sent to war in Iraq. "For all of his deviant behavior, he enjoys family life," says Kirk of his character. "He likes having the kids come to him for advice."

With its decidedly un-PC story lines, the show's success last season the comedy drew the network's largest audience, 1.6 million viewers a week came as somewhat of a surprise to Parker. "I thought people were going to be really offended by it," she says. But the actress, a veteran of film (Fried Green Tomatoes), stage (Proof, for which she won a Tony) and TV (The West Wing), is hardly afraid of taking chances. "It seemed a little to the left and just not very mainstream," says the South Carolina native. "That's why I liked it."

The show's collision of wacky and uncomfortable situations delivers a comedic hit that has people hooked. "It's our highest-rated show," says Showtime president Bob Greenblatt. "I think people identify with these characters. We thought people would reject the show because Nancy was selling marijuana. But they've gotten past that. They just see her stories as really relatable."

Even so, Nancy's single-mom skills have come into question by Parker herself. While filming the first season, she reportedly argued with series creator Jenji Kohan about Nancy's poor parenting. [Kohan declined to be interviewed.] But when asked about the tension, Parker insists all's well: "I just know that I work hard, and I don't want anything to get in the way of that."

A single mother, the actress chose to do the 12-episode show partly because it has a shorter shooting schedule, which allows her to spend more time with her 2-year-old son. She says she understands the stress her character is under. "Nancy's priorities are skewed, which is what happens when you're grieving," Parker says. "I don't think she's a bad person, because everyone fails. Being a mom is just a job that can't be done perfectly. I think she loves her children but she's at a point in her life where she's doing some questionable parenting."

And making some risky business decisions, like deciding to "grow" her operation with her own strain of ganja (the focus of this week's episode). "It's this massive undertaking, and she's got some questionable helping hands," Parker says, laughing. "She's in too deep."

We're ready to inhale.

How's it looking for Weeds' Elizabeth Perkins' (Celia) chances of taking home an Emmy on Aug. 27? TV Guide's Matt Roush reveals his predictions in the magazine's Emmy Preview issue, now on newsstands.

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