In the not-so-distant future, researchers at a deep-sea laboratory have finally succeeded in inventing a time machine. Heavily burdened by financial stress, head researcher Woo Seok is promised more funding from a mega-corporation, if he successfully completes a test flight. Ji Wan tries to stop his colleague and lover, Yeong Eun from going on the dangerous flight, but Woo Seok and Yeong Eun carry out the mission and travel to 11 A.M – the next day. They arrive at the planned time only to find the base on the verge of collapse. What could have happened in the 24 hours?