TONIGHT'S MUST-SEE

"Stargate SG-1" season-opener, 8 p.m., Sci Fi Channel. No one would have guessed that this sturdy, standard show would go on and on. It's starting its 10th season now; that tops the combined total for the original versions of "Star Trek," "Battlestar Galactica," "Batman" and "Buck Rogers." Created by Showtime and spun off from a movie, "Stargate" was sometimes too stiff. It's been boosted immensely by the addition of Ben Browder and Claudia Black, from the late, lamented "Farscape." Last season ended with the Ori mother ships coming through the supergate and shattering the good guys. Now Carter is floating in space, her air supply dwindling. Daniel has disappeared. Then there's Vala (Black). She's just given birth to a baby that will turn instantly into an all-knowing teenager. They always seem to. It's a big, busy episode with lots of action and some neatly dabbled humor.

OF NOTE

"24," 7 and 8 p.m., Fox. Both reruns have Jack desperate to get information from his old enemy, Henderson (Peter Weller).

"NCIS" and "The Unit," 7 and 8 p.m., CBS. These two military shows will remain on Fridays for a while, loaning their Tuesday spots to reality shows. In the "NCIS" rerun, blood is found in a lodge used by visiting Navy families. "The Unit" has an assassination assignment in Spain.

"Biography," 7 p.m. and 9 p.m., A&E. First is a portrait of Ken Jennings, the perpetual "Jeopardy" champ. Then comes a two-hour profile of game shows.

"Las Vegas," 8 p.m., NBC. Ed (James Caan) has left the casino and Monica (Lara Flynn Boyle) takes desperate measures to get him back. She offers a Porsche, a song by Robert Goulet and — in desperation — an apology. Meanwhile, there are preparations for a valuable gem; also, magician Criss Angel dazzles guests.

"Monk," 9 p.m., USA Network. Here's another of Monk's worst fears: Due to a strike, no one is picking up the garbage.

"Law & Order," 10 p.m., NBC. A promising, modest-income student is found dead after selling papers and test answers to classmates.

"Stargate: Atlantis," 7 p.m., Sci Fi Channel. Last season ended with the Wraith tapping into the alliance database. That let two hive ships head toward Earth wreaking destruction. There's some strong action tonight, plus solid drama (as Weir confronts her bureaucrat superiors) and even humor as the un-heroic McKay fumes about being captive. It's a good hour, except there's too much similarity with the "Stargate SG-1" episode that precedes it.