Farentino's break into show business came relatively easily with "Capitol", on which she registered high degrees of popularity with the fans despite the show's weak ratings. When the soap opera was canceled, she shifted to primetime, playing Susan Smith, John Ritter's sometime love interest, during the first season of the ABC series "Hooperman" (1987-88). From 1990-91, she was eager prosecutor Julie Janovich, who agonized over the rights of the very sleazeballs she was putting behind bars, in the low-rated, but critically applauded ABC drama series "Equal Justice". Farentino returned to series TV as the head of a group who break away from the controlled environment and form "Earth 2" (NBC, 1994-95). She also played the recurring role of David Caruso's girlfriend during the first season of "NYPD Blue" (ABC 1993-94), of which Gregory Hoblit was executive producer and a frequent director. Farentino has also appeared frequently in TV longforms, breaking into the genre with "She Was Marked for Murder" (NBC, 1988). Farentino played a descendant of Sherlock Holmes' rival Moriarty challenging the master sleuth in "1994 Baker Street: Sherlock Holmes Returns" (CBS, 1993). Additionally, she was Judalon Smyth in the 1994 CBS miniseries "Menendez: A Killing in Beverly Hills" and starred in "A Mother's Instinct" (CBS, 1996). Farentino returned to series work alongside Ken Olin and Jason Gedrick in "EZ Streets" (CBS, 1996-97) and in "Get Real" (Fox, 1999-2000).
Farentino made her feature film debut in the obscure, Italian-made "Cellar Dwellers" before starring opposite Brian Benben in "Mortal Sins" (both 1989). She played a girl in the elevator flirting with Warren Beatty in "Bugsy" (1991), Princess Yasmin in Blake Edwards' "Son of the Pink Panther" and a small role in "Malice" (both 1993).