* 30 Rock (9:30/8:30c NBC)
Is Liz's longstanding luckless romantic streak possibly behind her? Liz thinks she's met her Mr. Right at the dentist's office, and she now sinks her teeth into efforts to find him and win him over. Meanwhile, the rumor mill swirls that Sheinhardt Wig Company might be putting NBC up for sale, a development that upends Jack's well-tended world. Then there's Tracy, who goes on a quest to win a Tony Award. Elizabeth Banks returns as fetching CNBC host Avery Jessup. And Michael Sheen, who portrayed David Frost in the film Frost/Nixon, guest stars.
* American Idol (8/7c Fox)
The singers must face the music tonight. After enduring a three-week semifinal round packed with highs and woes (and even a medical scare involving contestant Crystal Bowersox), the remaining competitors anxiously await this results installment. America has voted, and four semifinalists will be sent packing. This leads to the unveiling of the Top 12 finalists, a jubilant dozen who will advance to the final round, which kicks off next week.
* Survivor: Heroes vs. Villains (8/7c CBS)
What is it with these veteran castaways? They're falling like flies. First, Stephenie dislocated her shoulder and Rupert broke a toe, both in the first challenge of the season. Next, Boston Rob passed out and required medical attention. And last week, crybaby Coach felt so disrespected by his tribemates that he threatened to quit. In this outing, another player suffers a serious injury during a challenge that could cause him or her to exit the game. And speaking of exits, Russell could become the next villain to get his torched snuffed since he continues to defy his team's orders to not search for the hidden immunity idol.
* Sober House with Dr. Drew (10/9c VH1)
Season 2's motley crew includes Alice in Chains bassist Mike Starr, basketball bad boy Dennis Rodman, Crazy Town's Seth Binzer (whose pseudonym is Shifty Shellshock), defrocked pageant queen Kari Ann Peniche, ex-madam Heidi Fleiss, tough-guy actor Tom Sizemore and porn star Kendra Jade Rossi. In the season opener, they all arrive at Dr. Drew's house of sobriety and meet the returning house manager, Jennifer Gimenez.
Season 7 has been a reality check for the clothiers. So far in this year's reality fashion foray, they've had to spin out garb from burlap potato sacks, create clothes as inspired by artwork, whip up red dresses for inspirational clients, and craft age-appropriate wear for little girls. Then there was heavy metal in last week's outing, in which they utilized unconventional hardware materials to produce fashion-forward looks. (Jay displayed mettle and emerged victorious.) It's another runway takeoff tonight when Jay and his fellow designers keep pulling strings in the season's eighth fashion challenge.