On the recent episode of SBS's variety show "Running Man" that aired on Dec. 30th, Lee Kwang Soo's pants fell off.

The cast were on a beach in Busan, completing one of their challenges. Lee Kwang Soo and Kim Joong Kook were facing each other off in a race, Kwang Soo was leading and he was about to win, when kim Jong Kook yelled "Pants!" but Lee Kwang Soo's pants were already down and his underwear was a little visible, so the editors covered it up with a smiley face.

This funny incident made the whole cast burst into laughter, as it is now so common for Lee Kwang Soo to show some funny trick.

Even if his pants fall off, Lee Kwang Soo was able to complete the challenge.

On this episode of 'Running Man' actress Choi Ji Woo was the star guest, her mission was to eliminate all of running man, however the real mission was to fool the actress herself.
The next episode of 'Running Man' will air on January 6th, with Yonghwa and Jonghyun from CNBLUE, Lee Kikwang from Beast, Simon D from Dynamic Duo, and Choi Ji Woo.