CINEMA: VALLEY OF THE DULLS

What gets a movie the dread NC-17 rating these days? Normally the reasons children are forbidden to see films are explicit sex and spectacular spasms of violence. In the case of Showgirls, though, the list of no-nos might read, "Obscene level of incompetence, excessive inanity in the story line, gross negligence of the viewer's intelligence, a prurient interest in the quick buck."

Showgirls, a Las Vegas sex-and-dope opera from the Basic Instinct team of Joe Eszterhas (writer) and Paul Verhoeven (director), is one of those delirious, hilarious botches that could be taught in film schools as a How Not To. It...