Gullible yet cheerful Shin Ji-Hyun (Nam Gyu-ri) is living a perfect life: she is the only daughter of wealthy, doting parents and surrounded by great, supportive best friends. She is also engaged to be married to the perfect man, Kang Min Ho (Bae Soo-bin), in just a few weeks. Meanwhile, Yi-Kyung (Lee Yo-won) is in an existential crisis following her boyfriend's tragic death. She works third shift at a convenience store, sleeps in the afternoon, and often spends what little time she has left in the day contemplating suicide.

One fateful day interweaves the two characters' stories as Yi-Kyung attempts to kill herself by walking into oncoming traffic. A bystander saves Yi-Kyung by pulling her out of harm's way at the last moment, but a massive pile-up ensues from her actions. Ji-Hyun is driving nearby and fails to brake upon approaching the collision site, crashing into a truck. When Ji-Hyun regains consciousness after the accident, she shockingly finds that she could neither make physical contact with the people crowding around her car nor could any of them hear her protests. She also sees her own body being carted into an ambulance. A motorcyclist seems to be the only person who can see her. The cyclist calls himself 'the Scheduler' (Jung Il-woo) and claims to be an angelic being charged with guiding souls to their final destinations.

Ji-Hyun leaves the cyclist to follow her body and watch as the paramedics attempt to revive her. Upon reaching the hospital, Ji-Hyun meets 'the Scheduler' again. He explains to Ji-Hyun that since it was not yet her scheduled time to die she is to be given a chance to recover from her now vegetative state and live. The offer is contingent, however, on completion of a mission. Ji-Hyun must gather a total of three teardrops from people who truly love her. She is additionally required to recover each tear from three individuals none of which may be a relative and do so within the next seven weeks. Ji-Hyun immediately thinks of her fiance and two best friends and is certain she will live again. Ji-Hyun then finds herself in the body of the suicidal Yi-Kyung for which she will remain for the duration of her quest.

Ji-Hyun proceeds by seeking employment as a waitress at a restaurant owned by her high school friend, Han Kang (Jo Hyun-jae). While in the process of obtaining her proof of employment at a hotel where the real Yi Kyung worked, Ji-Hyun's memory begins to return to her. Before the accident, Ji-Hyun had agreed to meet up with her best friend In Jung (Seo Ji-hye) to show her the bridesmaid dress Ji-Hyun had chosen for her. Ji-Hyun's elation is muted when she makes an earth-shattering discovery which opens her eyes to the deception around her. She soon realizes with painful clarity that her life was not so perfect after all and that it won't be as easy to find people who truly love her as she once thought.