Seo Jin-woo has a special condition called hyperthymesia which allows him to remember almost every day in perfect detail. His father Seo Jae-hyuk, on the other hand, has developed Alzheimer's disease, making him lose his memories. When Seo Jae-hyuk is wrongfully convicted of murder, Jin-woo vows to prove his father's innocence. Four years later, Seo Jin-woo becomes a lawyer to put real criminals behind bars, but bribery, corruption, and betrayal will not allow him an easy road to justice.