Actress Rose McGowan has sparked reports she is to wed director Robert Rodriguez, after she was spotted flaunting a diamond ring on her engagement finger. The screen beauty fell for the filmmaker on the set of this year's (07) Planet Terror, and the couple went public with their relationship in May - shortly after Rodriguez filed for divorce from his wife of 16 years, Elizabeth Avellan. MCGowan was previously engaged to rocker Marilyn Manson, reports the New York Post's gossip column, PageSix.