His early life was spent battling as a member of the notorious Hulltoon Huns in the 1980s.
But, in recent decades, Gary Carroll has been submerged in a very different kind of conflict, as a mercenary in the war-torn Middle East.
And now, aged 53, he is gearing up to tell all in an upcoming book, Mercenaries Of Baghdad, detailing his time working for a private security firm on the payroll of the American Government.
Most recently, he was on the frontlines of the fighting against Isis in Kurdistan in 2015 using his own money to pay for flights and bullets during the conflict.
The former para- trooper said the book had forced him to delve into some of the horrors he had witnessed, long since buried in his memory.
He has already contributed to a documentary titled The Mercynaries of War, but the book will be a more personal account of how he went from gang member to veteran para, before stints in the French Foreign Legion and his time as a soldier-for-hire.
Gary has promised the book will be a breakneck journey, which will appeal to veterans and civilians alike, where he will recount how he cheated death in some of the most hostile environments known to man.
This includes barely escaping with his life and suffering a broken back when a vehicle he was travelling in was badly damaged following an improvised explosive device (IED) explosion in 2007. Harrowing images in the documentary, show the devastation left behind by the roadside bomb.
Gary thanked documentary film maker, Mihail Kunchev, for visiting Scotland to allow him to tell his story of the battles he faced during convoy and life after the battle.
“We did the documentary last year but I’ve been compiling the book over the last nine years,” he said. “I had to cast my mind back to those events almost like I was literally back there.
“During my time I was in charge of a team of 14 before that incident in 2007.
“We worked with a number of nationalities and lost friends during operations and my own life was nearly gone when that IED went off.”
Bullet-ridden vehicles, torched cars and suicide bombers all became an every-day reality for the former Harris Academy pupil. During his time working on convoys he was involved in operations moving military officials and journalists from CNN.
Kidnapping and beheading, or a “skinhead”, with his grisly demise recorded and shared on the internet, was a prospect he faced every single day he worked with the security firm.
And this was the first thought on his mind when he regained consciousness after the 2007 explosion.
He said: “I still remember seeing the vehicle bouncing down the road following the explosion.
“When I came to my fear was of being taken prisoner.
“It was common knowledge at that time if you were captured in Baghdad you were going on the internet and would be a ‘skinhead’.”
Gary said the book, which is likely to be released in the autumn, will be an eye-opener.
He added: “From the gangs, to my time in the TA parachute regiment right the way through to the private security – I’m amazed I’m still here.
“When I look back at some of the pictures of my time across there it’s almost hard to believe.
“I’m hoping we can have the book out by October.
“It will portray the life of mayhem that I’ve led.
“There has been a great response to the documentary and the book is going to look at other experiences I encountered.
“I believe the book will be of interest to civilians as well as those with a military background.
“I’ve already released a few teasers of what is set to come. The response has been fantastic so far.”
Gary is still actively helping soldiers who have returned home from conflict.
To view the video on YouTube, search The Mercynaries of War – Combat Survival True Life Film.
‘I’ve spent a lot of my time helping others stay out of trouble’
There is no denying Gary “Taz” Carroll has lived a life of, to quote his own word, “mayhem”.
From one of the most notorious periods of gang culture in Dundee to the bloodied oil fields of Iraq, the hardened veteran’s story is a compelling tale.
Gary has now left behind the battlefield and found peace in helping others.
But while telling his story it becomes all too evident that memories of conflict are never far away from the grandad’s mind.
Watching the YouTube film documenting some of the fighting he encountered, it’s easy to see why.
The Mercynaries of War – Combat Survival True Life Film gives a hard-hitting account of what Gary saw first hand.
Like many soldiers, the former para found it hard to leave behind the conflict of war and immerse himself back into life within the confines of the City of Discovery.
The documentary on YouTube has already racked up a quarter of a million views to date.
The harsh reality of war is all too evident to see from the get go, with Gary’s own footage showing the harrowing and hostile environments faced on a daily basis by soldiers and private security firms.
But Gary said he is now focused on working with the young people in the city.
He insisted he was trying to keep kids away from the gangs, guns and knives and encouraging them to transfer all their energy into sports and fitness.
He said: “It’s very much a big part of what I do now.
“I’ve been helping raise monies to support the Skyaxe Combat & Fitness Centre.
“I’ve spent a lot of time now referring the young team away from the gangs, guns and knives to sport.”