The 80th annual “holiday extravaganza” features performances by Megan Hilty, Trace Adkins, Mariah Carey, Cee Lo Green, Rod Stewart and Il Volo, and the lighting of an 80 foot Noway spruce. The special is hosted by Al Roker and Savannah Guthrie. 8 p.m. Wednesday on NBC (seattletimes.com/tvlistings).

“The Andromeda Strain” (1971), 7 p.m. (TCM): Scientists rush to isolate an alien germ brought back by a space probe. From the Michael Crichton book.

“A Charlie Brown Christmas,” 8 p.m. (ABC): Charlie Brown and Linus search for the meaning of Christmas; the short “Prep & Landing: Operation Secret Santa” accompanies the holiday classic.

“Arrow,” 8 p.m. (CW): Oliver meets a mysterious woman with dangerous secrets.

“Invention USA,” 10 p.m. (History): Scotty takes on a tornado of dust and debris to test a product; an inventor believes he’s created a must-have product for campers.

“Love You, Mean It with Whitney Cummings,” 10:30 p.m. (E!): Mindy Kaling.

The New York Times