Clearly, the only thing better than winning “American Idol” is not winning.

Adam Lambert, runner-up of the most recent contest, returns to Fox to perform on the season finale of “So You Think You Can Dance” (7 p.m., Fox).

If you can’t name the actual winner of the 2009 “Idol” off the top of your head, or without resorting to a search engine, you’re probably not alone. By the way, it was Kris Allen, who now joins Jordin Sparks, David Cook and Taylor Hicks in the ranks of “Idol” winners not exactly on the tip of everyone’s tongue. To change all that, Allen will appear tonight on “Late Show with David Letterman” (10:35 p.m., CBS) along with Robert Downey Jr.

• “Great Performances at the Met” (8 p.m., PBS, check local listings) opens its 2009-2010 season with a new production of Puccini’s “Tosca,” featuring soprano Karita Mattila in the title role.

• “Modern Family” (8 p.m., ABC) repeats a Christmas-themed episode that reminds us why this comedy is nearly universally acclaimed as the breakout new series of the season. Like only the smartest sitcoms, “Family” blends the smart and even edgy with the sweet and occasionally touching without ever descending to blatant sentimentality. That’s a hard trick to pull off, but “Family” does so consistently and seemingly without effort.

Folks who missed last week’s “Family” may have been watching the fall-season finale of “Glee.” That musical melodrama won’t return to the Fox schedule until April 13.

• For every memorable holiday-themed special or episode, there seem to be at least five forgettable duds. And occasionally some rise to the level of memorably bad. As I’ve noted before, “Disney Prep & Landing” (7 p.m., ABC) — repeated for the third time tonight — is a terribly ill-conceived combination of Christmas, militarism and adult ennui. But for all of Disney and ABC’s efforts, I think it will simply vanish from our collective hard drives and never rise to the level of truly, unforgettably dreadful.

The same cannot be said of the 2004 comedy “Surviving Christmas” (9 p.m., TNT), possibly the worst-reviewed Christmas movie since “Santa Claus Conquers the Martians.” The holidays truly came early for film critics that year, offering them a chance to savage this Ben Affleck and James Gandolfini offering with rare gusto. The movie bible “Variety” called it “An almost mirth-free, poorly conceived comedy destined to offer Ben Affleck bashers satchels full of new ammunition.” Ouch! “Newsweek” described it as “formulaic swill.” The LA Weekly continued the gastronomic theme and pushed it away like a steaming plate of “Capra-corn gone rancid.” And “Entertainment Weekly” groaned weakly, “There are no survivors here.”

Now that’s a Christmas movie worth watching! At least once.

Tonight’s other highlights

• The judges pick the numbers for the five competing groups to perform as medleys on “The Sing-Off” (7 p.m. NBC). Two groups will leave tonight.

• An addict’s death may have been premeditated on “CSI: NY” (9 p.m., CBS).

• Roxie hosts a dinner-party setup for Jamie and Darryl on “Eastwick” (9 p.m., ABC).

Cult choice

Adrian Pasdar (“Heroes”) stars in the 1987 Western-vampire hybrid “Near Dark” (7 p.m., IFC), directed by Kathryn Bigelow (“The Hurt Locker”).