Engulfed by the darkness of doping's "white noise", he emerged the other side to become a beacon in cycling's anti-drugs fight.
And in a sport where the tainted legacies of former Tour de France champions Lance Armstrong and Jan Ulrich continue to cast a dark shadow, reformed rider David Millar can see a light at the end of the tunnel.
He has come a long way since nine years ago when he was was sitting in a Biarritz restaurant in south west France.
Millar was having dinner with Dave Brailsford, now performance director at British Cycling and Team Sky, when French police arrived to arrest the cyclist, throwing him in a cell and outing him as a drugs cheat.
A two-year ban from competition followed and, after a Damascene conversion, he returned to the sport a reformed character determined to remove the stain of doping from cycling.
"I was a fervent anti-doper," the Malta-born Scot, who spent his formative years in England and Hong Kong, told CNN's Changing Gear series before the start of the 2013 Tour de France.
"I was a naive kid who came from Hong Kong, who dreamed of winning the Tour de France and who was disgusted to learn that my colleagues were doping, but within four or five years I was one of them."
Millar had served notice of his potential by winning the prologue of his first ever Tour de France in 2000 and the journey from idealistic youngster to fully-fledged doper was not a simple one.
What began with "recup" injections of vitamins and iron -- not illegal in the sport but a practice Millar had long been opposed to -- ended with him intravenously pumping outlawed substances into his bloodstream.
"I was part of a culture where it was -- it was never obligatory, but it was -- I would describe it as white noise," explains the 36-year-old, who rode for the Cofidis team between 1997 and 2004.
"It was always there. It was in the background. It was something with a certain inevitability about it -- if I ever wanted to be the best and be professional.
"That unfortunately was the era I began my career in, and something that I regret deeply, and that's something that I have tried to rectify ever since.
"There are many of us that make mistakes that we regret ... that should never have happened."
Millar now rides for Garmin-Sharp -- the team formerly known as Garmin-Slipstream -- having also represented Great Britain at the 2012 Olympic Games in London. He sits 98th in the 2013 Tour de France after nine stages of the marathon race.
He is also a member of the World Anti-Doping Agency's (WADA) athlete panel and he has used his experiences to become an unlikely figurehead in the crusade against doping -- with the help of Garmin-Sharp general manager Jonathan Vaughters, who has also admitted that he doped as a pro cyclist.
"We started off at Slipstream, now with Garmin-Sharp, but we started off with a team with a pragmatic method," Millar continued.
"That method was originally to sign me as an anti-doper, as an anti-doping crusader who had been a doper ... it's not very logical but it was inspired by Jonathan Vaughters.
"We really have led by example. We're not going to rely on their anti-doping methods. We've said: 'We're going to do this ourselves' and we've been flag bearers ourselves for the sport."
What Millar hopes Vaughters has fostered at Garmin-Sharp is an environment in which a young, clean rider can harbor legitimate dreams of winning cycling's biggest prize.
While his early career led him down the wrong path, Millar's experiences have afforded him a unique insight which could prove invaluable to those who might be tempted to dope.
"I made the wrong decisions because I was surrounded by the wrong people in the wrong culture," declares Millar.
"But because of that, it's allowed me to understand that mentality and put everything into what we do with our team now. Our team is the total opposite.
"We create an environment for a young version of me to remain naive, be idealistic, and reach the Tour de France without ever encountering drugs.
"I'm very proud of that ... I'd like to think I'm a kind of example of the whole story."
The sport is now in a position where, according to Millar, it is creating icons such as 2012 Tour de France winner Bradley Wiggins, who won't be defending his title this year, and fellow Garmin-Sharp rider Ryder Hesjeda,l who can be admired and trusted.