Secrets of the Penguins cinematographer, Bertie Gregory, shares the memorable moment he filmed baby penguins leaping from a 50-foot cliff with PEOPLE.

The new National Geographic series, “Secrets of the Penguins,” premieres Sunday, April 20 at 8 p.m. ET. Stream the first ...

National Geographic celebrates Earth Month with some flightless, feathered friends in "Secrets of the Penguins," streaming ...