Curiosity Stream
Sign In

Secret Life Underground

2 episodes 97%4KCC

Descend beneath the surface to witness Earth's hidden engines of life.

Explore the subterranean systems that shape our planet, from soil organisms and fungi to cave species adapted to darkness and scarcity. As scientists reveal how roots, bacteria, earthworms, and isolated ecosystems work together, each discovery makes the world below feel more intricate and essential. Sign up to see the unseen forces sustaining life on Earth.

Episode guide

2 episodes
1
1Part 1: The Skin of the Earth
We know less than 10% of the organisms that populate the underground world and that, each in their own way, take an active part in creating the soil. We are just beginning to discover that plants form partnerships and create complex unions. Welcome to this subtle, surprising and secret world.
52 min
2
2Part 2: Hidden in the Depths
Take a journey alongside scientists into an underground maze with huge surprises in store. They lead us into monumental cavities, shaped by water and by time. They reveal to us mineral jewels of staggering beauty and shed light on certain species of fauna that defy the imagination.
52 min
Good to know

Frequently asked questions

Thousands of the world's best documentaries and factual programming — nature, history, science, technology, and biography — including exclusive Curiosity Originals like Secret Life Underground. Stream it all ad-free, anytime.

Plans are billed annually — every plan streams in 4K. The Smart Bundle adds four partner services. There are no contracts — cancel anytime.

Watch on the web, iOS and Android, Roku, Apple TV, Amazon Fire TV, Chromecast, Android TV, and most smart TVs. Start on one device and pick up right where you left off on another.

Yes. The library is full of family-friendly nature and science programming, and the Smart Bundle includes Kidstream — carefully chosen, ad-free shows kids will love and parents can trust.

Absolutely. There are no contracts and no cancellation fees — manage or cancel your plan anytime from your account settings.

Curiosity Stream is our streaming service — thousands of documentaries and originals. The Smart Bundle is Curiosity Stream plus four other independent streaming services (Tastemade, Kidstream, Curiosity University, and SOMM TV) on a single subscription.

Yes. Start on any plan and move up to the Smart Bundle whenever you like — the change takes effect right away, and your billing is simply prorated from your account settings.

Got your answer? Pick a plan and start streaming.Start streaming
Available now

Start watching Secret Life Underground today

Stream thousands of award-winning documentaries. Cancel anytime.

Start streaming