National Geographic has built a reputation for unveiling hidden corners of the animal kingdom through its acclaimed "Secrets of" documentary series executive produced by James Cameron. From elephants and whales to the octopus, each chapter goes beyond the surface to deliver cinematic, intimate glimpses of life in the wild, occasionally revealing never-before-seen behaviors. Now, the latest installment explores some extreme corners of the planet with Secrets of the Penguins — and it's already turning heads.