SEE ALSO: 'Iron Man' unveils character cut of Shin Se Kyung + BTS photos

Lee Dong Wook revealed his reason for choosing to star in 'Iron Man', sharing, "First off, the fact that my character has knives coming out of him from his emotional scars was very unique. I was very curious to how it would come out on screen and what it would be like to act it out. And Shin Se Kyung was cast before me so I wanted to act with her."

The onscreen couple also took a compatibility quiz. When asked, "Cola or cider?", they both answered chose cider, surprising themselves. When asked, "Transformers or Iron Man?", they chose 'Iron Man', of course. Shin Se Kyung then suggested the question, "Jjajangmyeon [black bean sauce noodle dish] or jjamppong [spicy seafood noodle soup]?", to which they both answered, "Jjamppong."

'Iron Man' will premiere on September 10 at 10 PM KST!