By Andrew Wallenstein
 
      Nickelodeon will protect its cable dominance with the afternoon addition of "Doubledare 2000" (weekdays, 5-5:30 p.m. ET, beginning tonight), a revival of the game show that helped build the network.
       Although Nick continues to sit atop the cable heap in total daypart ratings (a 24-hour average of 1.139 million overall households), ages 2-11 (1.195 million) and has led all cable channels in ad revenue since 1996, it's no time to rest on laurels. Nick finished fourth among all competitors in 1999 with a 1.9 primetime rating, but that tally is down 5 percent from 1998.
    What's more, fast-rising rival Cartoon Network is up 7 percent, with a 1.6 score.
        Don't think it desperate of the kid-friendly network to dust off an early mainstay like "Doubledare": When it first aired in 1986, afternoon ratings tripled within a month.
    "Doubledare" went on for 341 episodes over seven award-winning seasons. This time around, 65 episodes have been ordered, to be taped at Nickelodeon Studios Florida at Orlando.
        At first glance, "Doubledare" might look like your average game show. Two families compete against each other, answering trivia questions. But when a contestant doesn't know an answer, he or she can opt to take what Nick calls a "physical challenge," which entails performing wacky stunts that often take a turn for the messy.
      Multicolored slime has a way of spewing in every episode, as does the obstacle-course run that the winner must tackle at the end to earn extra prizes.
        For the millennium edition, Nick has instituted a Triple Dare Challenge, which is a stunt worth triple the points and triple the mess. 
   Also, "Doubledare" has a new host in Jason Harris, who replaces longtime emcee Marc Summers, who still serves as a consultant on the show. The series has brought back several producers from its original run.
        "Doubledare" will also be coupled with the hilariously named "Slimetime Live," a series of interstitials that will run in the preceding hour between 4-5 p.m. "Live" is an interactive  match-and-win game that pairs viewers with studio contestants who perform "Doubledare"-ish stunts.
      Whoever loses is subjected to the "Slime-U-Lator," which will undoubtedly whet viewer appetites for the goo to come.
    In short, "Doubledare" is good, clean but messy fun. The sanctioned sloppiness may even appeal to adult males 18-49, a demo where Nick has experienced an alarming 18 percent drop. 
    Another disturbing statistic that indicates all is not as peachy at Viacom's pride and joy: Total day share of youngsters slipped from 44.5 percent to 42.5 percent this year, according to Turner Entertainment, whose Cartoon Network jumped from 25.5 percent to 29.9 percent by the same measure.
   Nevertheless, 2000 should be a good year for Nick. Two more new series, "Caitlin's Way" and "ChalkZone" are on the way, as are the network's first forays into original long-form programming. Nick certainly knows how to launch new shows. The most recent addition, November's "Little Bill," drew 2.1 million viewers, a 134 percent boost among ages 2-11 in its Sunday, 8 p.m., slot.

-Andrew Wallenstein covers television programming for Media Life.