Matthew Broderick, Denzel Washington, Morgan Freeman. Directed by Edward Zwick. 1989. Rated

R. (RCA/Columbia tape, 122 min., Hi-Fi stereo, DS)

Movies with noble motives tend to trip over their high-mindedness here and there. Though this sometimes happens with "Glory," the movie is still a stirring experience -- particularly for viewers who were enthralled with Ken Burns' "The Civil War" on PBS -- and it transfers with undiluted impact to video.

During the Civil War, a special unit of the Union Army was formed of runaway slaves and freeborn blacks. The first such unit was meant to be only a support and ceremonial group. Soon, however, the men of the regiment were in the thick of combat. "Glory" (based on books by Lincoln Kirstein and Peter Burchard and the letters of Robert Gould Shaw) thrusts you into the thick of the fighting.

One of the reasons "Glory" works so well as a movie -- despite an intrusive score and a finale that would rival any Radio City Music Hall inspirational holiday show -- is the superb ensemble cast. Washington won a Best Supporting Actor Oscar for his portrayal of Trip, the angry Tennessee runaway slave-turned-soldier whose arrogance is eventually channeled into bravery on the battlefield. Freeman plays the more world-wise Rawlins -- the regiment's older, proud top sergeant who is quick to temper Trip's anger, especially in defense of the white Union soldiers who have been dying for him for three years.

Although Civil War buffs have told me they feel Broderick was accurately cast, he seems somehow out of the proper century to me, playing Robert Gould Shaw, the young white Bostonian appointed commander of the regiment. But just as Shaw was able to win the loyalty of his troops, Broderick will eventually convince you as to the true nature of Shaw's character.

Jane Alexander appears for an instant as Broderick's mother, in a role obviously left mostly on the cutting-room floor -- a terrible waste of a towering actress.

If you can ignore the way the music continually anticipates forthcoming emotions, you will be rewarded by a movie of undeniable power, especially in the depiction of the attack on Fort Wagner on Morris Island, South Carolina, in 1863. It is one of the most stunning battle sequences of any recent movie. Flaws and all, "Glory" is appropriately named.