Kathleen Robertson (born July 8, 1973, in Hamilton, Ontario) is a Canadian actress. She is best known for her roles as Tina Edison in the Canadian sitcom Maniac Mansion (1990–1993) and as Clare Arnold in the Fox teen drama series Beverly Hills, 90210 (1994–1997). Robertson also starred in a number of films, and from 2011 to 2012 played the role of Kitty O'Neill in the Starz political drama series Boss. In 2014, Robertson began starring as homicide detective Hildy Mulligan in the TNT series Murder in the First.