Seung-tae's not sure he's lived the best of lives. He's 70-years-old and still closeted, with no one left at his side to hold his hand when he's diagnosed with Alzheimer's. But maybe all that could change... with the help of his old diary. Turns out he can reach out to his 19-year-old self in the past via its magic. And talking to his younger self, all these memories keep coming back... Of how he was in love when he was so young, and how there was this serial killer on the loose in his neighborhood... (Source: Lezhin Entertainment)