Suddenly they were both attacked simultaneously by something invisible in the water.

First, anyone knew that something was wrong was when they saw the woman's lifeless body floating on the surface, where her body was recovered.

It wasn't bite marks they found but extensive blistering in the forms of linear welts across her body.

And this is precisely the hallmarks of the most venomous creature on earth box jellyfish.

My way to meet somebody who has made it his life's work.

To understand these near invisible killers, particularly how they're toxin works on humans.

Now he knows better than most what this actually feels like because he was one stung in the face on hospitalized for 50 hours, Dr Jamie Seymour has spent 20 years researching box jellyfish, attempting to understand their behavior and how their complex venom works.

To make anti venom, he has to collect live samples.

It's risky work in 100 plus degree heat handling the planet's deadliest creature.

I've never seen a box jellyfish, so I've agreed to help him collect samples from these ghostly killers with anti venom.

What makes them so dangerous to man or their tentacles on adult box jellyfish.

Congrats.

Up to 40 of them on each one contains around 5000 stinging cells that makes 200,000 deadly points of contact.

They can sense when they touch something.

Living from that triggers thousands of time darts.

Toxin, then enters the blood.

It takes only 6 to 7 feet of a single tentacle to kill an adult.

My wet suit should act as a barrier.

Water might look quite inviting, but Jamie tells me that just this little bit of beach here, there could be hundreds box jellyfish getting in without, um, due precaution and Jew vigilance would actually be verging on insanity.

So what you're looking for is how to explain it, but a transparent jelly fish with tentacles.

There's one right there, so it's just it's just a sort of a fuzzy wife.

But that purple this point dates give away.

But not all the animals had purple tinkles.

I don't hear you knowing that I'm just thinking you could come down here hot day.

Let's just specially the water cool off on DDE.

You could die.

You just need able gets in these sort of conditions.

No matter if you could do it, you will die if you're swimming in here and you didn't know it was going on, you got It's a simple as that The main reason we're here is to click.

Then what happens?

You grab the animal, you pick it up, you cut the tentacles off.

So we got about hot for the tentacles off.

Then we can take the tentacles back to the lab and extract venom.

What you need, remember is these guys will grow the tentacles back somewhere between half two and each in length a day.

So cutting off half the tentacles is not really a major issue for these animals.

They grow them that very, very quickly.

Jamie has learned that it is possible to gently grasp the jellyfish bites body without being stunned.

He tells me that to do this, you need the sensitivity and field that can only be achieved for using bare hands.

Oh, what's that?

Right in the end, that's a beauty.

Actually, that'll be a cracker, you see, So we're literally instead of needed water here, and it's almost impossible.

Assists.

You want to be in front of the animal it's gonna take to Haines.

Yes, and it will be a lot heavier than you think.

Okay, it's now or never.

Time to commit.

Wait a minute.

Touch something.

Yeah, that's 10 to go.

Radio only the briefest of touches.

It feels like my skin is on fire.

And that was with less than 1/10 of an inch of contact.

Yes, it started to burn.

It's dialing up a little bit.

Imagine 67 thinks that.

I mean, you probably quarter inch maybe.

Yes, darling, up a heck of a lot of start to get some indication of pain that goes with it.

Now, for me, I'd let that animal gonna go look for another one because it's got tentacles of things around.

It's Bill being no.

Okay, so leave that one.

One element of this is the pure sort of technical thing about picking it up.

But the the other thing that's there in the back of your mind, which you gotta stay there but it doesn't take over everything else is just how dangerous these things potentially are on its crocks.

Here.

It's very slippery underfoot as Muslims buzzing around.

It's it's, you know, staying focused on the heat as well, staying focused.

It's It's a lot to tonight.

I'm starting to think that I might not be up to the job, but I'm determined to try one more time.

This is now personal.

That one looked as we got over.

It looks bigger, actually.

Okay, it's more or less in a good position.

Isn't this a good one?

Done it, I finally overcome my fear.

Now I can get a good look of this deadliest of all killers.

It's strange it doesn't look alive, but it feels alive.

But in a very weird way that size animals probably got 78 tentacles on each corner of the belt.

You only need 6 to 7 feet long in an adult to kill somebody.

That animal has potential to kill 50 people in under two minutes.

We collect several more large specimens and harvest their venomous tentacles for making anti venom back of the lab.

I still can't compute the deadliness off the venom of this thing.

I mean, this is quite a big animal on.

This would kill several people on DDE in a very, very short time.

Having now felt what one of these things is like Okay, that was that was the very mild end of the spectrum.

But for that for that burns.

But making this sort of conceptual jump between that and somebody dead, how does the venom actually work?

You gotta remember first up that the venom is a component of several different things.

So what you got was the localized pain, which was destruction of cells.

So nerve pain there.

That's point.

What will also have happen is another component being deposited directly into your circulatory system.

Adelaide's your veins and arteries.

And that would have gone straight to your heart.

A big box jellyfish stung.

It hurts immediately.

It's like a red hot night dragged across your scheme.

So zero being no pain.

10.

The worst you can imagine.

My last trip, I did about 14.

If someone had hated me a loaded gun, I was off planet.

It is.

It's his pain.

It comes in and you get it under control and then it goes up a little and you get that under control and it goes up another level, and it just gets worse and worse and worse.