Horton Hears a Who! (8pm, NBC) - A 2008 computer-animated Hollywood update of the beloved illustrated children's book by Dr. Seuss. Horton, a thoughtful elephant living in the jungle of Nool, discovers that an entire society -- Whoville -- rests inside a speck. He gentle rests it on a clover flower and searches for a place where it will be safe from the perils of the world.
How the Grinch Stole Christmas! (8pm, ABC) - Another Dr. Seuss adaptation. This is Seuss' 1957 story about the Christmas-loving Whos of Whoville (see above) and the evil Grinch who hatches a plan to steal their holiday. Boris Karloff narrates this animated classic, which first aired in 1966.
How the Grinch Stole Christmas (9pm, ABC) - Yet another Dr. Seuss adaptation, this one a live-action version of Seuss' classic tale starring Jim Carrey, Jeffrey Tambor and Christine Baranski. Directed by Ron Howard.
National Lampoon's Christmas Vacation (9pm, ABC Family) - Family man Clark Griswold (Chevy Chase) is determined to stay at home and provide a warm, fun-filled Christmas for his family.
Rizzoli & Isles (9pm, TNT) - Dr. Hope Martin asks Maura a life-changing favor in the Season 3 finale. Meanwhile, Casey Jones prepares for surgery and Tommy shows off baby T.J. Before long, all attention turns to the collapse of a building, where loved ones are trapped inside.
Leverage (10pm, TNT) - Looks like this Season 5 finale is also the series finale. In tonight's last episode, which was filmed as a series finale, Nate takes on a case connected to his son's death and leads the team into one of its most perilous schemes. The show's executive producer describes the episode as "the most powerful episode we've ever done."