"An Actor is an Actor" is a movie to be released on October 24, 2013, starring Lee Joon. It's the third movie of the renowned Korean director, Kim Ki Duk, as a prequel of "A Movie is a Movie (2008)" and "Poongsan Dog (2011)." So Ji Sup in "A Movie is a Movie," and Yoon Kye Sang in "Poongsan Dog" garnered spotlights for their performances.

MBLAQ's Lee Joon, a singer who wanted to be an actor since middle school, is to perform the role of a main character of "An Actor is an Actor." He said he strongly argued with the agency to take this role. Lee Joon said, "I will balance the movie filming as long as it doesn't interfere with the MBLAQ's group activities."

Lee Joon said, "I've gotten frustrated when the scenes I thought I did my best don't come out well and scenes I thought I filmed standard seemed better on the screen." He added that he was able to center his energy with Kim Ki Duk's advice.

"Director Kim said, 'Doing well or not doesn't matter much. The heartbeat of an actor who has performed his role with sincerity is bound to be delivered to the audience through the screen.' It has encouraged me a lot, and helped me center my performance."

Oh Young, the character Lee Joon played, is a passionate actor wannabe. He, starting from his trivial supporting role, jumps up to the stardom in a flash and collapses to the bottom. He, who once thought good performance is all that actors need, realizes that sponsorship, relationships with the gangs, sex entertainment and tricks of agencies also play a role in the entertainment.