What's Worth Watching: America's Got Talent, an Oprah Winfrey Special, Mars, The Wall and more for Monday, December 19

Matt Roush
Trae Patton/NBC

AMERICA'S GOT TALENT -- "America's Got Talent Holiday Spectacular" -- Pictured: Nick Cannon --

America's Got Talent Holiday Spectacular (8/7c, NBC): Venturing outside summer programming for its first holiday special, AGT collects some of its most popular performers—including this year's winner, Grace VanderWwal, plus Season 5 winner Mat Franco, The Clairvoyants, Olate Dogs, The Regurgitator and Professor Splash, who dives into a pool of eggnog—for a true representation of what a classic variety TV used to look like, with magic, music and bizarre specialty acts.

First Lady Michelle Obama Says Farewell to the White House—An Oprah Winfrey Special (8/7c, CBS): In her final one-on-one interview from the White House and the private residence, the First Lady sits with the Queen of TV to discuss the last eight years and what comes next. Considering the most-quoted preview clip, in which Obama suggests, "Now we're feeling what not having hope feels like, it may not be her rosiest hour on TV. (The cynical among us might well wonder if the next First Lady will be taking notes.)

Mars (9/8c, National Geographic Channel): You certainly can’t accuse this series, a fascinating blend of current-day documentary and futuristic sci-fi, of sugarcoating the challenges and dangers of traveling to and colonizing the red planet. In the series finale, a tragedy at the Mars colony has people on both planets wondering whether to scrub the mission. In 2016 segments, SpaceX works to develop technology to get us to Mars. Should we be so brave.

Inside Monday TV: NBC previews a new high-concept game show, The Wall (10/9c), which plays out on a four-story wall where each correct answers sends a green ball down the edifice to add to a money pool, but get a question wrong and a red ball will fall to erase some of the sum. … History's This Is History: 2016 (10/9c) looks back at the year's highs and lows to put the more epic moments in context with other game-changing events within our lifetime. Don't expect consensus. … In a booking that seems inevitable, Neil deGrasse Tyson welcomes William Shatner to National Geographic Channel's StarTalk (11/10c) to talk all things Star Trek and sci-fi, answering fans' "Cosmic Queries."

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