Cornered Mother Penguin Confronts Hungry Sea Lion '70 Times Her Size' in First of Its Kind Footage (Exclusive)

The drama of the animal kingdom is more thrilling than anything you'll find on primetime TV.

PEOPLE has an exclusive clip from National Geographic's upcoming docuseries, Secrets of the Penguins. According to the show, the clip features a brave moment "never filmed before."

Secrets of the Penguins, narrated by Blake Lively, led by Bertie Gregory, and executive produced by James Cameron, provides an intimate look at how several penguin species survive in the wild and a world rapidly morphing due to climate change.

In PEOPLE's sneak peek at the three-part show, premiering April 20 on National Geographic, a mother rockhopper penguin faces a giant beast to ensure the safety of her offspring.

The clip begins with the penguin returning to land with a "full belly" after a swim near the Falkland Islands. The food she has collected from the water isn't for her, but for her newly hatched chicks waiting back at the nest.

As the mother rockhopper nears the shore, she tries to blend in with the other penguins returning from their hunts. Here, it is clear how the penguin species got its name, as the birds hop and jump along the rocks to move on land.

Unfortunately, the bird star of this clip falls behind, and soon finds herself being chased by a massive sea lion looking to make a lunch out of the penguins at the back of the pack.

The mother rockhopper tries to escape from the predator, but "she is completely out of hops," Lively narrates.

Instead of giving in to the sea lion and accepting her fate, a death that would doom her chicks as well, the penguin takes a bold approach.

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"This mother is a fighter," Lively says in the clip as the penguin turns around and faces the towering sea lion, who is "70 times her size."

What comes next is a "never filmed before" interaction between the two animals. The penguin stares at the sea lion, who is only inches away from her beak, and starts shouting at the giant marine mammal. She flaps her flippers and screams directly in the face of the sea lion until the predator backs down, seemingly shocked to be challenged by such a tiny bird.

This caught on camera first is one of several never-before-filmed moments captured for Secrets of the Penguins.

To learn more about this amazing creature and see how the mother rockhopper fairs after her sea lion encounter, tune into the 3-part docuseries, which premieres on National Geographic on April 20 and will be available to stream on Disney+ and Hulu on April 21.