At 14 years old, Yoo Se-yoon began to act strange blurting out nonsensical phrases and ekeing out bizarre, repetitive body motions. And although the behaviors faded with time, the terrible memory of the abnormal phase remains etched in the minds of his friends and family. Years later, Se-yoon has built a successful comedic career and a family of his own. But the unknowable thing that plagued him long ago is starting to return.