Fans and viewers are holding their breath for the premiere of the upcoming swimming movie "No Breathing" which features Seo In Guk, Lee Jong Suk and Girls' Generation's Yuri as its main cast.

During the October 22 press conference with the cast and staff, Lee Jong Suk admitted that Seo In Guk's body intimidates him. The actor said, "There were a lot of scenes that require us to be topless, so we were conscious of each other's bodies. Because I have thin bones, a thin body and pale skin, I worry a lot. Whenever I have a scene with Seo In Guk, I would look like a Q-Tip."

He added, "If I heard that he has skipped a meal, I would skip a meal as well, and I'd work harder to tone my body."

Similarly, Seo In Guk also admitted to some insecurities. He revealed, "I started off in a bad shape compared to Lee Jong Suk so I began working out in order to catch up. It was hard to work out and act at the same time. I had to control a lot of my eating habits while working out so I remember it being difficult."

"Also, he was taller and had better posture, so I tried to work on mine, but I didn't end up looking as cool as him."

"No Breathing" will premiere on October 30.