In the 80s, Down was seen in various ABC miniseries, such as "The Last Days of Pompeii" (1984), "North and South" (1985) and its two sequels "North and South: Book II" (1986) and "John Jakes' Heaven and Hell: North and South Book III" (1994). She earned a whole new cadre of fans when she took on one of the leading roles as the scheming rich bitch Olivia Richards in the NBC daytime drama "Sunset Beach" (1997- ).
Down broke into films with "The Smashing Bird I Used to Know/The School for Unclaimed Girls" (1969), about a girls reformatory. She was still playing juveniles in "Scalawag" (1973), in which her character and that played by Mark Lester were befriended by Kirk Douglas, leading to adventure. In 1977, she made her feature singing debut as the 18-year old virgin bride of an older man (Len Cariou) in Harold Prince's "A Little Night Music", based on the Stephen Sondheim-Hugh Wheeler musical. Down was the married British woman with whom Harrison Ford falls in love in the banal "Hanover Street" (1979). By the 80s, her film roles became sporadic and the quality dwindled. By the 90s, she was in such low-budget fare as "Munchie Strikes Back" (1994) and "Beastmaster III: The Eye of Braxus" (1995). Down was even leading lady to Hulk Hogan in "The Secret Agent Club"(1996).
Down's private life has often been fodder for the tabloids. She was romantically involved with screenwriter-director Bruce Robinson for nearly a decade before breaking it off with him to marry an obscure assistant director from Argentina. After less than a year of marriage, she obtained a divorce and married director William Friedkin in 1982. Their three-year union produced a son, Josh (aka Jack), who was the subject of a bitter custody battle which gave Down more publicity than most of her screen roles.