May is returning to Korea for the first time since her adoption for two reason: one, to find out the reason her biological parents abandoned her; two, to trace the origin of the mysterious lizard-shaped scar on her shoulder. Outside the airport she helps a taxi driver, En-seol, while he is suffering from a heart seizure. After this first encounter, En-seol is determined to help May in her search as his last good will. As the two lost souls embark on a journey to answer questions of personal demons, they start to realize that they are bonded by a source they are only slowly starting to uncover.