PLANET / EPISODE 01

There’s an Ocean
Hidden Inside the Earth

Hundreds of miles beneath our feet, evidence locked inside minerals points toward an enormous reservoir of water deep within Earth.

COMING SOON

THE EXPLORATION

What if one of Earth’s largest reservoirs has been hidden beneath us all along?

Episode 01 follows the evidence deep below the surface — from a tiny piece of ringwoodite to the mantle transition zone, where water can be stored inside the crystal structure of minerals under immense pressure.

This is not a buried ocean of open liquid water. It is something stranger: water chemically bound within minerals, with research suggesting that the transition zone can hold a vast amount of it.

FOLLOW THE EVIDENCE

The story behind the story.

Our source notes will live here alongside the episode so viewers can go beyond the documentary and examine the evidence themselves.

Ringwoodite

A rare mineral inclusion provided direct evidence that Earth’s transition zone can contain significant water.

Seismic Evidence

Seismic observations and laboratory work help scientists investigate hydration and melting deep within the mantle.

Transition Zone

The region roughly 410–660 km below the surface is central to understanding how water may cycle through Earth’s interior.

Full citations and source links will be published with the finished episode.

VISUAL & PRODUCTION NOTE

Some places can’t be filmed.

Past • Planet • Beyond™ may use illustrations, animation, visual effects, recreations, archival or stock material, and AI-assisted or AI-generated media to help visualize subjects that cannot be directly photographed. Representational visuals are used for storytelling and are not presented as direct documentary footage when they are not.

READ OUR EDITORIAL & CONTENT DISCLAIMER →

THE JOURNEY STARTS HERE

“THE CRAZY PART HAS TO BE TRUE.”

Wonder gets our attention. Evidence earns the story.

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