Critic's corner

9 p.m., Channel 56
Blair. Oh, Blair. What a mess you’ve made. Sleeping with Chuck, then getting back with Nate. Very impolitic. And now your father and his partner are in town, which always throws your mother for a loop. It’s just not easy being a Waldorf, is it?

10 p.m., Biography
Pre-Britney, the Monkees plied prefab pop to the people.

10 p.m., Channel 7
Tonight's the last time this time-travel tale will tug at your heart.

8:30 p.m., HGTV
A couple clean and clear clutter from their condo.

10 p.m., Channel 5
Have you never been mellow, President and Mrs. Bush? Olivia Newton-John performs for the first couple at the famous theater. Also bringing season's greetings tonight: Yolanda Adams, Jon Secada, Christopher Titus, and Wynonna.

8 p.m., Channel 4
Gracious, cherished, Jimmy Durante sure had a schnozz.

10 p.m., History Channel
Giant freshwater fish that will fully freak you out.

 Comcast
In the waning days of East Germany, a surveillance expert for the secret police (Ulriche Muhe) finds himself drawn into the life of the playwright he’s watching (Sebastian Koch). It's like "The Conversation" with a century's worth of nagging political resonances, and writer-director Florian Henckel von Donnersmarck neatly balances sentiment and suspense. An Oscar-winning audience pleaser. In German, with subtitles. (R, through Jan. 22) - Ty Burr