THE image is etched into Glenn Dickson's brain.
It's the moment a spearfishing trip with mates turned to horror as a 3.5 metre bull shark attacked.
"I felt a massive pull and shake, and I knew I was being attacked," Glenn tells 60 Minutes' Peter Stefanovic in an exclusive interview airing on Sunday night.
"It was kind of slow motion as I watched blood rise ... the image is imprinted in my head ... I remember watching the shark through my blood."
It was February 18 this year and Glenn was in the water with three mates off Hichinbrook Island near Cairns in far north Queensland.
As he swam upwards after spearing a parrotfish, the shark struck.
He knew, he says, even as the shark turned away it was going to come back.
As he half-scrambled, half-swam to climb a rocky outcrop, the monster hit again.
Metres away in their boat on the other side of the rock, mate and former Navy master diver Rick Bettua heard a muffled scream.
Rick, Peter Kosica and Aaron Butler knew before they looked what had happened: less than a minute earlier Peter had emerged form the water having seen the huge shark, but they were briefly separated from Glenn.
What they was horrific. "The water was bright red and he was trying to climb his way up a rock face," Rick says.
"His body was moving the way a body shouldn't move. The shark was shaking him."
Time may have slowed down for Glenn, but his three mates knew there was not a second to lose.
Hauling him into the boat, their worst fear was "that he was a goner from the waist down".
They remember he was white, drained of all colour ... and strangely, almost smiling.
Glenn knew he was in deep, deep trouble.
He remembers being punched in the chest as Rick, calling on three decades of weekly medical training, desperately made him respond - open his eyes, focus.
"You have to go back to your family," Rick said.
"You're not dying today."
He should have. The femoral artery is a large artery in the thigh which is the main blood supply to the lower limb. Rupture it and you can bleed out in as little as three minutes.
Glenn's three mates tell 60 Minutes of the frantic efforts to save him.
They were 40km from land in a small boat. Another 180km from the nearest hospital.
Along the way, Glenn "died" six times, Rick estimates. It came down to seconds.
"He had a 360 degree cut around his thigh, and every artery severed," Rick says. There was another massive gash on his calf.
"It came down to seconds," Rick says, remembering applying the first tourniquet, which did nothing to stem the flow or bring colour back into his mate. With the second tourniquet he coughed and screamed.
"I could have gone to sleep," Glenn says. "I remember having the choice." He also recalls Rick saying "can you feel the pain?" and focusing on his breathing, the pain, staying awake.
"I got colder and colder all the way up my body ... my breath started getting shorter," he says.
He thought about his family. That got him through.
Peter pushed the boat to its limits as they sped towards land, and Aaron, when they finally got into phone range, rang triple-0.
His words: "He's not in a good way, he's not in a good way," interspersed with apologies for yelling, taken from the taped triple-0 call, show the desperation of the men.
Even with the marina in sight they still thought they'd lost him.
A lone paramedic joined the rescue effort until the rescue chopper arrived.
Four hours later, the pain killers had well and truly kicked in. As they wheeled him from the chopper into Cairns hospital, Glenn can be heard yelling "I will survive". The song, he says, just popped into his head.
Meanwhile, Glenn's fiancee Jessie-Lee, mum to their young son and daughter, thought she'd lost him.
"I didn't want to go near him ... it frightened me," she says of seeing him at the hospital.
"He told me he will survive and asked me for a kiss." Glenn says he didn't know if it would be their last.
They amputated his leg the next day. He says it was fine, in exchange for his life.
Two months on, 60 Minutes reveals there are more battles ahead.
Rehabilitation has begun. Centrelink's rejection of a disability pension was "a kick in the guts" but again, his mates have stepped up. He's determined to walk again, to take Jessie-Lee down the aisle.
"Everything I took for granted now I have a moment and think: "I'm lucky to be able to do this again," he says. "So life's great".
60 Minutes airs at 8.30pm on Sunday on Channel 9
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