As Graham MacIndoe sat in his cell in New York's notorious Rikers Island jail in 2010, he had hit rock bottom.
After growing up in Armadale and Broxburn in West Lothian, he had studied painting at the Edinburgh College of Art and photography at the Royal College of Art in London. He then moved to New York to follow his dreams.
Those dreams became a reality. Graham travelled the world to take portrait pictures of celebrities including Michael Jackson, Tony Bennett and the White Stripes for Q magazine, The New York Times and the Guardian.
Graham had it all, but the pressures of his life resulted in an addiction to alcohol, cocaine and heroin. He was eventually sent to jail for four months for drugs possession, and spent a further five months in an immigration detention centre.
"I was drinking heavily," reflected Graham.
"People were doing drugs - something I had never done before. I was just like 'I'll try that'.
"What started off as partying and using sometimes with friends turned into a real serious habit, which turned into addiction and then became something I was totally incapable of dealing with."
The instinct of a photographer never left Graham, even at his most vulnerable point. As he spiralled further and further into his bleak, lonely addiction, he started taking pictures of himself. He didn't do it for anybody else, or for any reason, but - like many artists before him - he just instinctively expressed what was happening to him through his work.
Graham MacIndoe: Coming Clean is an exhibition of 25 of these photographs, and will be on display at the Scottish National Portrait Gallery until November.
Graham said: "I caught a glimpse of myself in a mirror once, when I was in somebody's apartment when people were using drugs.
"I looked at myself and thought 'Wow - this is how bad I look'. I realised that photographing myself was more relevant than photographing other people."
Annie Lyden, International Photography Curator at the National Galleries of Scotland, said: "One of the compelling reasons for acquiring the works was they are really like nothing else I have seen.
"As a subject, you see it appearing in the history of photography. There are plenty of photographers who turn their attention to drug-taking, but normally the position is one of voyeurs and what was so interesting about Graham's work was that the camera was turned on himself, so there wasn't any sense of him exploiting anybody at their weakest and vulnerable moments.
"It was him in control entirely and, therefore, it was a rare insight into what his life was like."
With the help of his partner, the journalist and author Susan Stellin, he managed to escape the vicious grip of drug addiction.
Graham has been clean for nearly eight years and is back taking pictures of the world's most famous faces such as actor Matthew McConaughey. He also teaches photography at Parsons college in New York, the city he lives in with Susan.
The pair wrote Chancers: Addiction, Prison, Recovery, Love: One Couple's Memoir about their story.
Susan said: "I first saw these pictures when Graham accidently posted some online. It was during the period when we were not together.
"When I first saw them, it was really devastating for me. This was his life that I hadn't been privy to. I am really proud that he has put them out there and the reaction has largely been very positive."
Graham added: "I am certainly not glamorising it. I'm showing it, very bare bones, as to what it was like for me.
"What I really want people to take away from it is you can fall really far but you can get back on your feet and get clean and healthy and find recovery."
- Graham MacIndoe: Coming Clean will be on display until November at the Scottish National Portrait Gallery in Edinburgh