TONIGHT'S MUST-SEE

"30 Rock," 8:31 p.m., NBC. TV has had its funniest moments when a key character turns tipsy. In these politically correct times, the trick is to have it happen by accident.

"Three's Company" once did that via plane-trip medication, with wonderful results. Now "30 Rock" does the same.

Nervous about a flight, Liz (Tina Fey) takes pills offered by Jack. That's a bad idea.

It's great fun to see this smart, cautious character acting loopy — especially when she meets Oprah Winfrey.

And there's a terrific twist. This one is a classic.

"Independent Lens: Knee Deep," 12 a.m. (Friday), PBS. There's an appealing, straightforward quality to the Maine people we meet here. Josh Osborne calmly explains why he wanted his mother killed; others, including his then-girlfriend, verify that.

But who fired the first shot? No one seems to know, but it's a fascinating journey, ranging from funny to heartbreaking.

OF NOTE

"Ugly Betty," 7 p.m., ABC. Betty's working overtime to draw the attention of a cute neighbor. Also, Amanda — suddenly broke and homeless — is her new roommate.

"Kath & Kim," 7:30 p.m., NBC. Kim isn't sure about returning to her husband. To keep him on edge, she tries speed-dating.

"CSI: Crime Scene Investigation," 8 p.m., CBS. Grissom needs help from his friend Lady Heather (Melinda Clarke). The case seems to involve domination, which is her specialty.

"Grey's Anatomy," 8 p.m., ABC. The residents are in another competitive frenzy. Also, Erica finds that one of them has a link to a longtime patient.

"The Office," 8 p.m., NBC. The annual customer survey brings surprising results.

"ER," 9 p.m., NBC. Banfield brings more ill feelings, this time for Morris and Neela.

"Life on Mars," 9:01 p.m., ABC. Sam was accustomed to 2008, with quiet racial relations. Now, back to 1973, he finds prejudice among police colleagues and violence between blacks and Puerto Ricans.