Usually by the second sequel, the best ideas are exhausted. And usually when it comes to Christmas TV specials, producers delude themselves into thinking audiences crave another version of "A Christmas Carol."

Credit DreamWorks' zany "Madagascar" series for ignoring the usual. "Merry Madagascar," airing Tuesday, Nov. 17, on NBC, is a delightful adventure with the Central Park Zoo menagerie still marooned on the island of Madagascar.

Just as Alex the lion, Marty the zebra, Melman the giraffe and Gloria the hippo (voices of Ben Stiller, Chris Rock, David Schwimmer and Jada Pinkett Smith) take flight in a hot-air balloon to return home, crazed lemurs shoot them down.

The lemurs mistake the airborne animals for the "midnight marauding red goblin" that drops coal on them. Soon, Santa (Carl Reiner) alights, and they capture him. Everyone knows no good could come from harming Santa.

The special, though only 30 minutes, has the hallmarks of the "Madagascar" movies: It's fun and clever. Also, the animated animals clearly have back stories.

"He started out as a performer, an actor and a New Yorker," Stiller says of Alex. "I was very comfortable in his world, a city dweller guy. That was always the way in for me to understand how to be a lion reconnecting with his roots. ... He keeps the others together. He's a good guy and gets stressed out."

Alex has reason to be stressed. Santa's head injury triggers amnesia, and Alex realizes that if the animals deliver Santa's gifts, that on his way home, Santa might drop the animals off at the zoo. Meanwhile the reindeer and the penguins bicker, an age-old feud that dates back to when Santa switched poles. Soon Santa joins the happy animals dancing to the films' signature, "I like to move it-move it," and it's funny to see Santa shake his substantial booty.

As they set out delivering presents, Melman tries going down the first chimney, gets stuck and whines that he's claustrophobic. Marty tells him "Now you can be Santa claustrophobic."