Margot Robbie may be the woman currently earning plaudits as comic-book character Harley Quinn, but Sara played the role long before her. She starred as Quinn in a TV series of 'Birds of Prey' in 2002. Her biggest 90s role was in 'Timecop,' which earned her a Saturn Award, but she hasn't appeared in TV or film since 2012. She'd been winding down her career for some time, with only a handful of appearances of any kind since the turn of the century.
She's still only in her early 50s, but it may be that she's decided to retire and settle down with her husband Brian Henson - the son of Jim Henson, who created the Muppets. Being married to the son of someone very famous isn't new for Sara - she was also married to Sean Connery's son Jason from 1996 to 2002.