Masterpiece Theatre’s four-hour production of “Anna Karenina,” adapted from the novel many critics say is the greatest of all time, is a visually masterful and beautifully acted work that comes as close as TV can to capturing the essence of the original. Filmed on location in Poland — in weather seemingly as severe as Russia’s in winter — the two-part miniseries stays true to its form as a magnificent love story that details what happens when passionate, unbridled romance blooms, then dies, while its protagonists must continue to live on in the world they have created for themselves. Leo Tolstoy wrote “Anna Karenina” in the late 19th century after he had finished his masterpiece, “War and Peace.” The novel’s opening lines set the stage: “Happy families are all alike. Every unhappy family is unhappy in its own way.” The Masterpiece Theatre production takes viewers from the heights of passion to the depths of tragedy in this story of Anna, perhaps literature’s most famous adulteress, and Count Vronsky, the golden-blond Russian cavalry officer who falls hopelessly in love with her. Providing the backdrop for Anna and Vronsky’s torrid affair are Anna’s callous husband, Alexei Karenin, along with Levin, a patrician farmer (whose character Tolstoy based on himself), and Levin’s love interest, Kitty, who is jilted by Vronsky once he meets Anna. Oblonsky, Anna’s brother, figures prominently as an unprincipled go-between, introducing characters to one another as they whirl their way through the rigidities of Russian high society. Executive producer George Faber and screenwriter Allan Cubitt wisely decided to cut through the complicated prose of the original and give the characters lines that ring with modern idiom. Wisely, the two also decided to cast the drama with unfamiliar faces instead of the usual costume-drama regulars. However, the production retains the visual imagery that Tolstoy created — palatial architecture and interiors decorated in impeccable 19th-century taste, mammoth steam-powered trains that move the story inexorably to its tragic conclusion, and a rich palette of color that accents the dramatic contrasts of the story. The frosty breath of carriage horses points up the passion Anna and Vronsky share, while the flash of skates and the spray of cut ice are metaphors for their violation of society’s rules. An impossible golden light suffuses the initial encounters of the two principals, and impenetrable winter darkness veils their final sorrow. Helen McGrory (Anna), Kevin McKidd (Vronsky), Douglas Henshall (Levin) and Stephen Dillane (Karenin) make their characters breathe fire and ice without a trace of apparent effort, and director of photography Ryszard Lenszewski creates a cinematographic epic full of unexpected and intriguing touches that would stand up to frame-by-frame examination. This joint British-American production lives up to the Masterpiece Theatre name and will provide a love story in two consecutive Sundays that will call for a