John Hopkins

He has just achieved an elite status.

At this point, more people have walked on the surface of the moon than have ever successfully dived to these sorts of depths.

He is now nearly as deep as the Eiffel Tower is tall.

Dave swims slowly forward, sweeping his torch from side to side.

Only the third diver in history to reach the bottom of this extraordinary cavern.

But then his light catches on something unexpected and shocking.

Encased in scuba diving gear, the body is lying on its back, its legs outstretched, its arms floating.

Exposed to the water, its head and hands are mere bone.

Yet a diving mask is still strapped disquietingly to its skull, the face turned up towards the black void above.

Barely hesitating, Dave abandons his exploration and swims towards the body.

He wraps his arms around it and tries to lift it from the silt.

But it won't budge.

Already over his maximum time at this depth, Dave has no choice but to turn and begin his long, treacherous journey back to the surface.

But not before attaching his cave line to the body so that it can be easily found again.

At around 140 meters, he meets his close friend and frequent dive partner, 48-year-old Don Shirley, who has been acting as his support today.

Dave manages to communicate what he has found, and Don gravely acknowledges.

He shakes his friend's hand, then leaves Dave to continue his ascent to the surface.

But they will both be coming back here soon.

Wordlessly, almost telepathically, a decision has already been communicated between them.

What neither man can know is the unimaginable impact this decision will have on so many lives, or the tragically high price which will be paid as a result.