Actress Sharon Stone's sexy sequel to Basic Instinct has been hit with an NC-17 rating in America for graphic sexual content, including an orgy and a threesome.

BASIC INSTINCT 2: RISK ADDICTION has received one of the most restrictive ratings for US cinemas, which bans anyone under 17 from seeing the film.

Producers have returned to the editing suite to tone down the controversial scenes in a bid to score a more audience-friendly rating.

The original movie was also given an NC-17 rating, forcing film-makers to cut sexy scenes.

Stone reprises her role as femme fatale Catherine Trammell in the sequel, and is joined by British actor David Morrissey, who plays a London detective assigned to evaluate her mental condition.

The sequel is scheduled to hit screens in the US on 31 March (06).