Opera is an acquired taste, they say, but represents a grand mix of music, theater and choreography. PBS tonight offers a grand opportunity to acquire an appreciation for the form.
* "Backstage/Lincoln Center" (7:30 p.m.-8 p.m., Channels 22, 67) -- Music is best heard when you know something about it. This pre-production special takes a look at Verdi's "La Traviata," composed in 1853. The opera's original working title was "Amore e morte," or "Love and Death," but official censors in Venice forced it to be changed to the final title, which means "A Fallen Woman." PBS.
* "New York City Opera, 'La Traviata' " (8 p.m.-11 p.m., Channels 22, 67) -- Janice Hall, Stephen Mark Brown and Louis Otey sing featured roles in this "Live From Lincoln Center" presentation, staged by Renata Scotto and conducted by Yves Abel. Performed in Italian with English subtitles, the opera is introduced by host Hugh Downs. PBS.
* "Raising Cain" (8 p.m.-10 p.m., Channel 45) -- Brian De Palma directed this movie chiller, in which John Lithgow plays a child psychologist who kidnaps his own daughter and frames his wife (Lolita Davidovich) for the crime. Fox.
* "Frasier" (9 p.m.-9:30 p.m., Channel 11) -- Faced with vague threats from his anonymous No. 1 fan, Frasier (Kelsey Grammer) hires a bodyguard (guest star Alyson Reed) but doesn't necessarily feel any safer. (And in the eerie Can-This-Be-Coincidence? department, John Lithgow of the just-mentioned Fox movie provides this week's celebrity caller voice.) NBC.
* "NYPD Blue" (10 p.m.-11 p.m., Channel 2) -- This series' other continuing romantic story is played more for laughs than the Andy/Sylvia relationship (Dennis Franz and Sharon Lawrence). In this repeat, the tryst of Greg and Donna (Gordon Clapp and Gail O'Grady) suffers a crisis of trust when her sister Dana (Debra Messing) comes on to Greg. ABC.
* "Vanishing Worlds" (9 p.m.-10 p.m., The Discovery Channel) -- The first installment of a four-week series -- documenting cultures around the world threatened by modernity -- focuses on the Himba, a traditional tribe in Namibia whose society centers on raising cattle. DSC.