TONIGHT'S MUST-SEE

"30 Rock," 8:30 p.m., NBC. Midway in this hilarious rerun, Jerry Seinfeld asks: "What's happened to this network?" It's a good question in the show and in real life. NBC crashed from first to fourth in the ratings, while offering a sea of so-so shows. Fortunately, Thursdays are an exception, with great moments. In this rerun, Liz returns from her summer hiatus to find an angry Seinfeld and a bloated Jenna, who ate her way through "Mystic Pizza: The musical."

"Splash" (1984), 6 p.m., WE. Tom Hanks keeps choosing the right movies and working for the best directors. Here's a prime example. In "Splash" (which repeats at 8:30), he finds a mermaid (Daryl Hannah), and is directed by Ron Howard.

OF NOTE

"CSI: Crime Scene Investigation," 7 and 8 p.m., CBS. With no "Survivor" for six weeks, CBS throws in reruns that form a two-parter. In the first, the identity of the "miniature killer" has been discovered and Sara is missing. In the second, the team races to find her before she dies in the desert.

"Clash of the Choirs" finale, 7 p.m., NBC. By the end of this hour, we'll know which choir has won $250,000 for a local charity. Before that, there should be lots of chances for singing. A feel-good show tries to end on a high note.

"Blazing Saddles" (1974), 6 p.m., AMC; and "Napoleon Dynamite" (2004), 7 p.m., Comedy Central. This is a big night for comedy movies, including those mentioned earlier. Watch one; tape some others.

"Grey's Anatomy," 8 p.m., ABC. In this rerun, the other residents are impressed by George. They don't know he's repeating his residency, after flunking the exam.

"Without a Trace," 9 p.m., CBS. A maintenance guy is missing and two laid-off workers are suspects.

"The Office," 9 p.m., NBC. After worrying that the office is cursed, Michael plans a fun run.

"Private Practice," 9:02 p.m., ABC. How unpopular was "Big Shots"? Even with three new episodes left, ABC has dumped it. Filling in are reruns of this show — which also has reruns on Wednesdays. Here, Addison throws a party for co-workers, but gets no RSVPs.

Make a difference. Donate to The Advertiser Christmas Fund.