REALITY. America unceremoniously sends one singer home, while you better believe mentor judges Christina Aguilera and Cee Lo Green will get a fireworks display of a farewell as they temporarily leave the show to promote a new album (Xtina) and work on a sitcom for NBC ("The Lady Killer"). Oh, yeah — and a Season 3 winner will be announced! Terry McDermott, Cassadee Pope and Nicholas David vie for that $100,000 recording contract.
Season finale, 9 p.m., NBC
"Ramsay's Christmas Cookalong"
SPECIAL. The only donkeys in this culinary-themed Christmas special hosted by hot-tempered "Hell's Kitchen" star Gordon Ramsay are the ones in the manger scene — not in his kitchen, for a change.
10 p.m., BBC America
"Mankind: The Story of Us"
DOCUMENTARY. As man conquers new frontiers in the 19th and 20th centuries, war and devastating effects on the environment are results. Will humans survive? Guess you have to watch!
Season finale, 9 p.m., History Channel
"NCIS: Los Angeles"
DRAMA. Spending Christmas at headquarters is at least better than spending Christmas on an aircraft carrier investigating the death of a fellow NCIS special agent, right? Um, right?
9 p.m., CBS