Han Se-joo, portrayed by Yoo Ah-in in Chicago Typewriter, is a renowned bestselling author in modern-day Korea. In his past life during the 1930s Japanese occupation of Korea, he was a writer named Seo Hwi-young. Despite his success, Se-joo struggles with depression and severe writer’s block, preventing him from completing his next novel. His life takes a turn when he encounters Jeon Seol, a fan and veterinarian, and Yoo Jin-oh, a mysterious ghostwriter. Together, they uncover secrets from their past lives and navigate the challenges of their intertwined destinies.