Mathapoo, which is about spreading happiness.
Nagaraj made his debut with Dinamdorum in 2000, but after his first directorial venture, he fell ill because of the addiction. All these years, he was battling with the addiction and trying to recover.
"I have been through the darkest days of my life. I don't want to look back, instead want to focus on what is ahead of me. I have learnt about life the hard way... My focus is on my career now," Nagaraj told IANS.
"Everybody in the industry encouraged me. Director Bhagyaraj sir personally congratulated me for making a comeback. I would personally like to thank so many people in the industry for welcoming me with arms wide open," added the director who got into the bad habits during his teenage years.
Mathapoo, featuring Jayan, Uday and Gayathri, is nearing completion. It is produced by Sudalaikannan and has music by K Velayudham.
"The film revolves around the importance of happiness in life. The hero wishes to spread happiness in the lives of everyone around him. In the process, he helps the heroine and her family in finding happiness and meaning in their lives," he said.
Queried if the film has been inspired by his own life, he said, "The search for happiness is more or less a universal theme. We are constantly in search of happiness, but seldom do we find what could really make us happy."
Nagaraj is known for writing dialogues for Tamil films Minnale and Kaakha Kaakha.