Los Angeles ? The day after filming wrapped on her first season of “Charmed” last spring, Rose McGowan dyed her hair a flaming red.

The producers were not pleased.

Actress Rose McGowan laughs on the set of Charmed.

She had been very much the brunette as Paige Matthews, one of three witchy sisters on the WB’s one-hour supernatural drama. How would they explain the change?

“Oh come on now,” McGowan told the producers. “You explain a lot of goofy things, goofier than this. Just say I did a spell or a potion which blew up in my face and turned my hair red.”

Though her suggestion was a joke, “that’s essentially what they did.”

McGowan’s determination to have a new look is one way the 27-year-old actress says she is coping with the “boot camp” confinement of shooting a weekly series. She’s even tried hypnosis to be “more accepting” of the rigorous process.

Currently in reruns (7 p.m. Sundays), “Charmed” also stars Alyssa Milano and Holly Marie Combs as Paige Matthews’ two half-sisters. It begins its fifth season with a two-hour episode Sept. 22.

McGowan, one of the stars of the 1996 hit thriller “Scream,” joined “Charmed” after last year’s departure of Shannen Doherty.

Like Doherty, McGowan has a bit of a bad-girl image, built in part by her brief engagement to shock-rocker Marilyn Manson and renegade roles in films such as “The Doom Generation” and “Jawbreaker.”

Still, directors John Kretchmer and Mel Damski, both on the “Charmed” set on a day of shooting back-to-back episodes, said that persona doesn’t really represent the person.

“Rose is so antithetical to what the public perceives,” Kretchmer said. “She’s an intelligent, worldly, sophisticated, educated woman who has an innate sweetness. I don’t see anything bad.”