This was the final film in director and screenwriter Ha Yoo's "street series" trilogy, after Once Upon a Time in High School: The Spirit of Jeet Kune Do (2004) and A Dirty Carnival (2006). He called it "a story about people who are used, then discarded, about lives that are, like the buildings they live in, unauthorized. [...] represents the obsession over land from which we are born, to which we return when we die. It is a feast of all things wretched."
Ha Yoo originally didn't want to cast Lee Min-ho in the leading role, finding Lee's breakout performance in TV series Boys Over Flowers "a bit cheesy" and that the actor was "so handsome he was like a manhwa character." But after being convinced by his wife, Yoo realized the potentially huge impact of "flower boy" actors completely transforming their image, and together they collaborated to "burn to the ground" Lee's previous screen persona as a chaebol's son.
Ha Yoo also asked actor Kim Rae-won to shed 15 kilograms since his character works as a rag man in the beginning of the film; Kim lost the weight in one month, which he said also made his fist-fighting scenes as a gangster more realistic.
One of the Soundtracks used is "Anak" by Freddie Aguilar from Philippines
This movie story similar to indonesian movie, Serigala Terakhir (2009)