n Christine Baranski, the actress who plays wisecracking sidekick Maryann in the sitcom Cybill, had better watch out. Her days may be numbered: if she continues to upstage the show's star, Cybill Shepherd, she may find herself being booted out - a fate which has already befallen Shepherd co-stars whose popularity has begun to rival hers.

n Cybill Shepherd is still best known for her role as the dizzy detective Maddie Hayes in the hit show Moonlighting. During its four years Hayes bickered and sparred with business partner David Addison, played by Bruce Willis. And bickering didn't end when the cameras stopped rolling. In fact, according to co-stars, it was the temperamental nature of the stars - especially Shepherd - that triggered the show's demise.

n Between the end of Moonlighting in 1989 and the start of Cybill in 1995, the 48-year-old actress made a handful of films and launched a singing career, but she remained in the public eye largely through her big mouth and on the subject of her big breasts, which she would discuss at any opportunity. She could also be relied on for a ridiculous quote on any given issue. In 1993 she told a gay magazine: ''I had this really strong feeling on the recent gay rights march on Washington that Jesus would have been marching too''.

n Born in Memphis, Tennessee, Shepherd began a modelling career in her teens (during which she had a brief affair with Elvis) and won her first movie role after director Peter Bogdanovich spotted her on the cover of a magazine. He cast her as the town flirt in The Last Picture Show (1971) and they embarked on a stormy seven-year relationship. They made a string of disastrous movies together before splitting up.

n Twice-married Shepherd has three children: a daughter, Clementine, from her first marriage, and twins, Ariel and Zachariah, from her second. She has said that the character she plays in Cybill is how she would be now had Moonlighting not come along - unmarried with two ex-husbands, several children by different fathers, and struggling to make it as an older actress in Hollywood.

n A new series of Cybill begins on Channel 4 at 9.00pm.

Alison Kerr