IN THE WAY WEST, AN AMBITIOUS UNdertaking for PBS's The American Experience, filmmaker Ric Burns (The Donner Party) assumes a larger canvas, one worthy of his older brother and fellow documentarian Ken (The Civil War, Baseball). This six-hour history, airing over two nights (Mon. and Tues., May 8 and 9, 8 p.m. ET), details American expansion from Missouri to the Pacific Ocean in the years 1845-93. During that turbulent, sanguinary era, settlers and adventurers tamed the vast continent while displacing and devastating the Native American population. The film takes the now-familiar Burnsian approach: a large and evocative assemblage of photos, knowledgeable talking heads (including authors Thomas McGuane and Ian Frazier) and readings from pertinent period texts. Along the way, some of the era's most influential and colorful figures—such men as Gen. George Armstrong Custer, Sitting Bull, Crazy Horse, Buffalo Bill Cody and Red Cloud—are tellingly profiled. The resulting opus is comprehensive but glum (a mood underscored by consistently plaintive music). As early as the prologue, the film's narration cites "the promise and sorrow of the American dream." The Way West is a rich, though rueful, history.