The first time Sarah Butler read the script for I Spit on Your Grave, Steven R. Monroe’s tense, unrelenting remake of the notorious 1980 rape-and-revenge thriller Roger Ebert deemed “a vile bag of garbage, reprehensible and contemptible,” she made an urgent call to her manager.

“I’d auditioned for it, but when I saw the script I decided to skip the callback,” says Butler, 25, best known for one-off appearances on CSI: Miami and CSI: New York. “All the nudity, violence, graphic rape scenes – normally, my manager is very protective of me, but he asked me to read it again, so I did. He said it could be the role of a lifetime, and I tried to look at it from that perspective.”

Butler eventually came around, intrigued by the chance to test her limits on screen. She plays Jennifer, a novelist on a solo writer’s retreat in the woods who is beaten and repeatedly raped by five pitiless hillbillies before turning the tables on her attackers. Butler didn’t seek out Camille Keaton, Buster’s grandniece, who played Jennifer in the controversial original, but the two enjoyed a chance encounter at Toronto’s Fan Expo in August.

“It was very cordial, but it didn’t seem like she really wanted to talk about the film,” Butler says of Keaton, who had her own serious reservations about starring in Grave, which she has described as a “bad cold” that wouldn’t go away. “I didn’t ask for her blessing or anything like that. We talked about normal things – she told me a story about her cats.”

Although Keaton was never sure that her R-rated version would see the light of day – and when it did, she was sure it would disappear quickly – the original, initially titled Day of the Woman, acquired a cult following, as much from Ebert’s now-famous review as from critics who proclaimed the film a feminist landmark.

Monroe’s update will be released this Friday without an MPAA rating, ensuring that few theaters will take a chance on a movie sure to arouse the ire of those who see it as lurid exploitation. (In San Francisco, it will open at the AMC Loews Metreon.) Yet Butler credits Monroe, producer Lisa Hansen and the film’s distributor, Anchor Bay Entertainment, for having the guts to go with an uncensored cut.

“In movies, it’s far more acceptable to depict murder than it is to show nudity,” says Butler, who says Monroe, “a real family man,” made her feel surprisingly comfortable about shedding her clothes for the camera. “The MPAA wanted us to make a thousand changes, but Steven thought, as I do, that it would really cut off the movie’s legs.

“I look at it this way – a lot of movies that try to depict real-life events go for an R rating, or maybe PG-13, but how real is it? People want reality, but they get uncomfortable when films show the bad side of reality. We wanted to stay true to Jennifer’s experience, or the experience of any woman who’s been in that situation. It’s difficult to watch, but if you’re going to commit to seeing a movie like this, don’t go out for popcorn during those scenes.”

The big test for Butler came in Los Angeles at the movie’s red-carpet premiere, attended by her parents. Her mother had planned to avoid it, reluctant to see her daughter violated on screen, but ultimately couldn’t stay away. Yet it was her dad’s reaction that Butler will always remember.

“I went to him after the screening, and I could see his eyes welling up with tears,” she says. “I felt awful. I said, ‘I’m so sorry to put you through that, I know how horrible it must have been to watch.’ And he looked at me, and he said, ‘No – that was really good acting.’ That was a moment I’ll never forget, and I cried too.”

Butler, currently searching for her next project, says she promised her parents the next movie would be a romantic comedy or maybe an adventure – she doesn’t want to be too closely identified with genre movies about horrific cruelty and victimization. But she is immensely proud of her work on Grave.

“I see the feminist aspect of it,” she says, addressing the mixed reaction of critics to both the original and Monroe’s remake. “I also see it as the story of someone who has very bad things happen to her and refuses to accept it. She fights back. You can call it horror, and someone told me they thought it was exploitative, but I don’t see it that way. It’s very real, and sometimes reality is ugly.”