ACTRESS Demi Moore, wife of Bruce Willis, is currently proving no slouch herself in the superstar stakes. She makes no secret of her lofty ambition. Seen recently as the clairvoyant in The Butcher's Wife , Demi does not believe in doing things by halves. From all accounts, she is now determined to equal her husband's fame. Now she's the star of the thriller Indecent Proposal , which could revive the flagging career of male co-star Robert Relford (who stepped in smartly when Tom Cruise dropped out after his conversion to the religion of Scientology appeared to prick his conscience). Demi is generally regarded to be a smart cookie, fiercely ambitious and a real go-getter. Like most major stars, she has her own production company, whose first project, Mortal Thoughts , co-starred her with husband Bruce. There was no such involvement in her next starring film, The Butcher's Wife , directed by Britain's Terry Hughes. Demi Moore has ruffled a few feathers on her way to the top, but she believes it's her own integrity that's at stake and speaks out boldly for her rights. She's 29 now, has mothered two children by her second husband, Bruce Willis, and has been acting in movies since she was a teenager. Of her own nomadic childhood, Demi says: ''I was born in Swell, New Mexico, but my family moved around a lot. As a wild guess, we must have moved about 48 times. We re-located at least every six months, which meant I was never in less than two schools a year. That's an awful lot of different schools. All that travelling around had a critical impact on me.'' I was 15 when I started to think about acting as a career. ''We were living in West Hollywood, and I left school the following year. I was always interested in performing but I didn't break into acting at first. I was 17 when I started modelling. ''At 5 ft 6 in, I wasn't considered tall enough for doing high fashion, but concentrated instead on the beauty market along with some commercial work for European magazines.'' She and Emilio Estevez became an item, in Tinseltown parlance, and were together for three years. Everyone thought marriage was definitely on the cards until Demi dramatically called off the wedding at the last moment after the invitations had gone out. She even starred with Estevez in another film, the police thriller Stakeout which also toplined Tom Berenger. Ironically, it was during a preview screening of Stakeout that Demi met Bruce Willis for the first time. Four months later, after a whirlwind courtship even by Hollywood standards, they became man and wife. Four years, and two children later, they are still together. Leaving his television Moonlighting success behind him, Willis has starred in two Die Hard mega-hits plus the more recent The Last Boy Scout , while Demi has soared to new heights playing Molly in the supernatural blockbuster Ghost opposite Patrick Swayze as her dead lover. Of that film's success, she explained: ''I think that when we've lost someone we all feel the desire for them to be back. Molly was given the opportunity to experience a last goodbye and be reassured that where he's going is a place of love.'' Demi's films post-Ghost have not been so successful.