Freaked-out fans and crusty critics alike will have plenty to say about "Slither," the unabashedly icky flick from writer/director James Gunn. Some will call it a horror movie, some may call it sci-fi, and others might even call it a comedy.

It's all good, said star Elizabeth Banks, as long as they don't assign it the demeaning letter that indicates second-class status.

"I wouldn't say it's a B movie," said Banks, who's best known for her role as the party girl from hell in "The 40-Year-Old Virgin" and appears in the forthcoming "Spider-Man 3." (see " 'Spider-Man' Secretary Dishes On Hero's Hookups, Black Suit"). "I mean, the B-movie genre is one of the things that James wanted to mainstream. It's just a really entertaining, original movie."

For further proof of the film's originality, Banks gave a plot breakdown about a small town overrun with slugs: "The slugs are a product of the alien. The alien, he can create wombs out of people. So one of the ways he infects people is he pumps them basically full of his fluid and makes them into a womb. And inside this womb grow these slugs. The slugs, they infect people by basically jumping into their mouths, and they go into your body, and once they are inside of your body, you become a zombie basically."

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Slugs and aliens and zombies? Oh my, indeed. But, Banks said, horror and sci-fi fans won't be the only ones sucked in by "Slither."

"Honestly, the reason I wanted to do the movie was because it was the funniest script I had read in a really long time. It is truly hilarious," said Banks, who plays the loyal-but-dim Starla. "It's an issue of tone. James is a really great writer; he's very good at setting tone and mood and creating a world in which these characters can live. The whole thing felt very much like a Coen brothers movie to me. It felt like a 'Fargo.' "

So, imagine William H. Macy getting blown up into a mucus-filled balloon, or Frances McDormand fighting aliens, and maybe you're on the right track. "Our movie harkens back to movies like 'The Thing' and 'The Blob,' " Banks said. "You have a more surreal take on being scared, basically. ... 'The Hills Have Eyes' and 'Hostel' and 'Saw' and 'Saw II,' they're all much more graphic and realistic. It is really somebody sawing their hand off or these guys living in this hostel. Our movie doesn't take itself that seriously.

"It's more that they are gross than scary," the actress said of the slugs. "People just get really grossed out. There's a great line in the movie: 'What kind of thing wants you to eat it?' Because the slugs go right for your mouth, and they try and get into your body. When you think about that, it's really disgusting."

Describing her character as "ambitious, smart white trash," Banks said Starla is a bit more layered than your average screaming blonde.

'Slither': Slime Time
Try not to hurl after watching these exclusive video clips and more from the slug-infested flick

"Starla grew up in a house with no mother and a drunk and abusive father. And she marries Grant, who's much older than her," the actress said of her ill-fated onscreen hubby, played by "Mallrats" villain Michael Rooker. "I don't want to say she was a gold digger, because Grant wasn't especially wealthy or anything. ... When this scenario happens, when her husband gets infected by an alien plague, she realizes that she can use his love to manipulate him."

A lot of actresses probably wouldn't have loved the "Slither" set, a collection of bloody props and body parts. For the tough-to-scare Banks, however, the surroundings made her feel right at home.

"Somebody asked us once what it was like to be standing around covered in all this crap," she said. "We would get to the trailers every morning and see the transformation happening. And then we would get to the set and people would literally place bloody pieces of brain all over us. Then we would stand around and drink coffee and hang out for a couple of hours. We got acclimated to each other being covered in gore and disgustingness.

"We were slathered with KY Jelly," she said. "I had these tentacles wrapped around me for most of the movie. It was all kinds of fun."

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