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Director Lee wasn't shy to show his fanboy love for 2PM's Junho. He said, "I liked Junho the best." He continued, "I was originally Junho's fan. I said that I liked Junho the best when 2PM first came out. It's because he has the face of an actor. He's usually stylish, and he has a cute face. He's the actor who synchronizes best with my movie character." 

The director also discussed how the three main leads suited their characters overall as he said,  "The three characters have nerdy personalities. These three [actors] appear to be inappropriate [for the roles], but after thinking about it and meeting them, I found that they were satisfactory. It wasn't difficult [to film with them]." 

Director Lee appeared particularly happy over casting Kim Woo Bin as he said, "Previously, Woo Bin acted in many serious roles, but this role needs a light-heartedness and playfulness; I thought it would be nice if I used him." He concluded, "I trapped him well. I used him well," causing laughter at the conference. 

'Twenty' is a film that follows the story of three friends experiencing the embarrassing age of 20. It is set to premiere in March.