Beforemanruledtheworld,Earthwasalandofgiants.Countdownthebiggestbeastsoftheirkindtoeverroamtheplanetinthiseye-openingoriginalspecial,anduncoverthesecretlivesofthesesuper-sizedspecies.Birdswithplane-lengthwingspans,dinosaursrivalingaBoeing737;thisstunningCGIspecialgoesinsearchofthetruthbehindthesemonsters,countingdown...