we think of the beach.

But I'm speaking to one of a handful of people

who have been to the deepest depths of our oceans.

(phone rings)

- [Bruce] My name is Bruce Strickrott,

and I am currently the senior pilot

and manager of Alvin Operations Group

at the Woods Hole Oceanographic Institution.

- [Narrator] Phew.

He pilots a submarine called Alvin,

and he works with scientists to explore

deep ocean life and terrain.

- [Bruce] Yeah, our average depth on most dives

is between 2,500 and 3,000 meters.

- [Narrator] That's almost two vertical miles.

This is what it feels like

to go 10,000 feet below the water's surface.

- [Bruce] We dive, often, down near the equator,

so it's bright and sunny.

It's early morning, it's nice.

You'll dive in the water and you hit a color of turquoise

that I have never been able to see anywhere else.

- [Narrator] But that blue doesn't last long.

- [Bruce] It's easy to lose light

within five to ten minutes, easy.

- [Narrator] And you're left suspended

in seemingly black water.

- [Bruce] The sub spins the whole way down

and the whole way up, but you don't even notice.

The only way you can tell is,

you can look at the compass and see it's turning around.

- [Narrator] Within that darkness, small flashes emerge.

These are from animals who live at these extreme depths.

- [Bruce] You hit lots of bioluminescence.

The amount that you can see outside is astounding.

- [Narrator] And then you hit the bottom.

- [Bruce] When you get to the site

that you're headed to and you turn the lights on,

there's a huge wow factor there.

- [Narrator] In particular, areas with geothermal vents

or these underwater geysers, massive structures

that rise thousands of feet up towards the surface.

- [Bruce] The view out the front

is astounding because there's nothing like it

anywhere else on the planet, nothing.

Our perspective is altered by our experience

because you can't go and look at the ocean anymore

and think of it just as this endless, flat surface of water.

You have an understanding of what's underneath it.

(inspiring music)