Choi Min-ah visits her father's office and enters a strange machine, undergoing a transformation. Choi Sun-man and Ko Baek-joong panic to find an answer.
Sun-man and Baek-joong try to track down the man who delivered the machine. They soon learn about a scientist who may know about the machine's origins.
After an arduous night, Baek-joong and Sun-man meet with Dr. Yoo's old lab assistant. Back in the office, they discover someone's been after their machine.
After Yoo Tae-man steals the machine, he inadvertently brings back a long-lost figure. Baek-joong and Sun-man meet the two men, but with a cautious guard.
Following Baekjung's departure, Baek-joong and Sun-man endure a decades-long wait. Upon Baekjung's return, he offers a tough decision about Min-ah's fate.