“Angels in America” (7 p.m. Sunday, HBO) is a television event. And, like any milestone, one approaches it with both happy anticipation and sober obligation.

This is, after all, director Mike Nichols’ six-hour adaptation of Tony Kushner’s Pulitzer, Tony and practically every other major award-winning play, featuring a dazzling cast of heavyweights including Al Pacino, Meryl Streep and Emma Thompson. It features a riveting story, frank and edgy dialogue and situations, occasionally poetic and exalted language, and a range of scenes and performances that can only be described as operatic.

Set in the 1980s, when AIDS was running rampant and still considered largely untreatable, “Angels” follows several overlapping stories.

The first three hours of “Angels” will air Sunday, followed by the concluding three hours Dec. 14.

• Thirty years is a long time to keep a secret. And two hours is too much to devote to “Word of Honor” (7 p.m. today, TNT), a grim military-justice drama starring Don Johnson. Three decades after a hospital massacre, a cancer-ridden Vietnam veteran (John Heard) spills the beans about his company’s murderous behavior, triggering a Pentagon prosecution of their former commander, Ben Tyson (Johnson). He’s currently a corporate hotshot whose wife, Marcy (Sharon Lawrence), is a school principal and pillar of the community.

After the revelations of the alleged war crimes, Ben and Marcy fall victim to a predatory press. Reporters dig up Marcy’s juicy past, which includes dalliances with every hair band of the ’80s. This ludicrous plot point hardly distracts from the dull heavy-handedness of a consistently unpleasant film. It drags on like a drawn-out, subpar episode of “JAG.” TNT will repeat “Word” at 8 p.m. Sunday.

Today’s highlights

• Kansas State takes on Oklahoma in the Big 12 Conference football championship (7 p.m., ABC).
• Whoopi Goldberg, Joan Cusack and David Arquette star with Kermit the Frog, Miss Piggy and the gang in the 2002 holiday special “It’s a Very Merry Muppet Christmas Movie” (8 p.m. NBC).
• The Rev. Al Sharpton is host of “Saturday Night Live” (10:30 p.m., NBC), featuring musical guest Pink.

Sunday’s highlights

• Judy Garland stars in the 1939 musical fantasy “The Wizard of Oz” (6 p.m., WB).
• Alan bends the rules on “The Practice” (9 p.m., ABC).
• “101 Celebrity Oops!” (9 p.m., E!) — the first of a five-night countdown — catalogs memorable gaffes, mistakes and arrests among the rich and famous.