KEY POINTS:
The past five years of Jason Adams' life play out like a blood-thirsty action movie crossed with the drug-fuelled script from Trainspotting.
It's hard not to wince as he describes the beatings he inflicted on other men, and those he took in return.
His aggression was fuelled by pure methamphetamine - first smoked and later injected.
The kick boxing enthusiast found he would attack for no reason.
"I found P and violence went hand in glove. It brought out a violence in me that towards the end was out of control. I couldn't stop kicking and kneeing people. My own brothers. I began to be a menace around people. I began to become unpredictable and uncontrollable."
Once he split open a man's head with a jack handle. Another time he took too much P and drove his car into a group of eight people.
His own head was later slashed open in a hammer attack - five blows to the skull and two to the body.
Jason, 35, thought it was a joke and left the blood from his wounded head splattered around the walls.
The hammer attack was retribution during a "P war" going on between two gangs on the North Shore, he said.
As Jason's P use propelled him further out of control, he began mutilating his body by thrusting hot knives into his chest.
"It was the only thing that purged the unclean feeling in me, to burn it out."
His family abandoned him and he had little contact with his children, now aged 12 and 11.
Jason said he always had a problem with drugs and describes himself as an addict for 20 years. He tried to kick the meth habit and would get clean for a few weeks but "something would come up and I would fall back to it".
The violence escalated to a point where Jason said he felt a total loss of control. He would find himself assaulting someone without realising he was doing it.
Incredibly, he was never arrested. The beatings were within the drug underworld and his victims never laid complaints.
He started wearing an old flak jacket that might protect him from a stabbing or being shot with small calibre ammunition. The hammer attack, for which he still bears the scars on his shaved skull , was a turning point.
"That got me thinking. I knew in my heart it was time for a change. I found it a bit of a joke at first but it wasn't until I came down off my cloud that I realised I was pretty lucky. I had a broken mind and a broken head from a hammer. It was time for a change."
He went to a detox centre in Auckland but was kicked out after a week for "minor offences". And one week in rehab was not enough to keep him away from the drug, which he returned to using last Christmas.
His salvation, he says, came in meeting a friend of Tony Romero, an American pastor who has established a New Zealand branch of Victory Outreach Church. The church has an addiction programme for men based at Romero's Otara home.
Jason spoke to the Herald seven months into a nine month rehabilitation programme with Victory Outreach.
Romano is a former meth addict from San Diego who kicked the drug after joining the church in his late teens. He said Jason came to his family "at the end of his rope".
Jason now joins other recovering addicts going out to the streets to talk to drug users and the homeless.
In a few months, he will leave the Romano home and move away from Auckland to reconnect with his children. He said he would remain with the church and wants to help others.
"A year ago I used to be a hunter of men, now I'm a fisher of men. I used to hunt men down and destroy them. Now I'm fishing for men to bring them in and give them the chance of salvation like I've had."
