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, Young-eun from going on the dangerous flight, but Woo-seok and Young-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?