CNN has gotten incredible access for the first

time, going deep inside captured Hamas tunnels.

In fact, the first western television crew allowed to go

inside Khan Eunice was our Nick Robertson, and he got

a rare look at where hostages were held underground.

And as part of this access, which did come from the

IDF, it is important that you know that CNN did agree

to report from Gaza under IDF s escort at all times.

As a condition for journalists to join the embed

with the ID, media outlets must submit footage filmed

in Gaza to the IDF for security review.

Now, CNN did not submit its final report

to the IDF and retained editorial control.

But we want to be very transparent with you.

Nick Robertson is out front with this incredible report

that you will see first out front, Han Eunice.

A gunner's view driving in,

scouring the landscape for threats.

Problem for these IDF troops, their

enemy is mostly hiding in tunnels.

They say the biggest issue is the fact

that we're actually maneuvering above ground underground.

Goldfuss, who commands Israel's biggest

military division ever, is adapting.

So you use all your sensors that you have.

You use your vision sensor, you use

your feel sensor, your smell sensor.

He has invited CNN to go deep into the tunnels.

We are told this is the heart of

Hanunis and that hostages are likely underground nearby

and that some were held here.

This tunnel we're going in here is one

where some of the hostages were held.

That first round of hostage releases, some

of them came out from down here.

So how deep does this tunnel go?

Our first time to get up

close to what's shaping this war.

We are moving underground.

We are maneuvering underground.

We are going to reach each and every

militant or each and every terrorist underground.

No modern army has had to fight

above ground and underground like this before.

How is that to do it?

It's difficult, and it's just going to be

a very, very hard, long fight to see

just how hard he takes us deeper.

So we came down a metal ladder.

We've come down one flight of stairs.

We're going down a second flight of stairs here.

A double flight, it looks like.

And down here, command and control

wires running all the way down.

It's a deep, deep system.

How deep are we underground, do you think?

Right now, at the moment, we are more

or less between ten to 15 meters underground.

Ten to 15 meters.

And now we're going down

another level, down more steps.

We're about to go down again.

Another level.

So low, my head keeps banging off the roof.

What are we looking at here?

This is a small room with

some kind of air ventilation system.

Air ventilation system that goes up

and metal frame around the door.

These metal frames, this can be as

much as this is a small room.

This is how the different cages

that they put the kidnapped.

So they were held in cages.

In cages, yeah.

Hidden and utterly cut off.

And down here you really can't hear anything.

What's going on in the outside world now?

We must be 20 or 30 meters down.

We're almost 20.

Almost 20.

So they have tunnels three times as deep as this.

What's clear here?

The money, planning and preparation

invested for a long siege.

We're 20 meters underground here, 20 meters.

And there's a fully flush toilet, and it's even painted

as placed for a light bulb and light switches, tiled.

The labyrinth keeps going.

Okay, now it's so low getting down

on our knees to get through. All right. Yeah.

Goldfuss pauses, lays out his

path to victory underground.

It's Hamas, and we have to reach

this Hamas core to finish them off.

But those palestinian people above

ground are also dying still.

I understand that. I understand.

That's why we're trying to do it as fast as we can.

Yesterday there were mortars and rockets fired from north

of Gaza into the civilian part of Israel.

So as long as those rockets are coming out of

northern Gaza, the people of the south who have moved

to the south can't go back to the north.

As long as we haven't carried out our mission

all the way, as long as we haven't finished

this mission, I don't think we'll leave here.

We head back half an hour underground.

We've seen only a fraction

of this war changing labyrinth.

Goldfuss's challenge, find all the others.