The encounter between a marine biologist and an octopus while on a crab hunt off the northeastern coast of Australia has been chosen for a new National Geographic documentary series. The three-part series "Secrets of the Octopus," which was produced by James Cameron and narrated by Paul Rudd, looks into the mysterious lives of these smart sea animals.

The show's main character, marine biologist Alex Schnell, spent two years shooting octopus behavior in ten different places around the world. The team got some amazing footage, like an octopus sleeping with rapid eye movement, putting on elaborate courtship shows, and using a shell as a shield to protect itself.

In the Great Barrier Reef, Schnell became close with an octopus named Scarlet, which was one of the most memorable events. Schnell saw Scarlet hunting with coral trout while the movie was being made. This is a rare sighting in the woods. Schnell even tried to talk to Scarlet by pointing to hidden crabs while they were hunting. The octopus reacted, which made people even more interested in how different species can talk to each other.

The documentary, which airs for the first time on April 21 on National Geographic, gives viewers a unique look into the interesting world of octopuses and the relationships they have with people.