With the latest 3D technology at their disposal, directors Neil Nightingale and Barry Cook take viewers millions of years back in time in the upcoming adventure Walking with Dinosaurs: The Movie. Following the final poster that debuted yesterday, 20th Century Fox has released the third trailer for this epic adventure, which follows two brother dinosaurs who confront a different species they have never encountered in the Arctic. Take a look at the latest footage before checking this out in theaters December 20.