Kotaro Koizumi, the son of former prime minister Junichiro Koizumi, plays against type in the new mystery series "Namonaki Doku" ("Unnamed Poison"; TBS, Mon., 8 p.m.), based on a story by Miyuki Miyabe.
Saburo (Koizumi) rescues Nahoko (Ryoko Kuninaka) from a molester and they start dating, but it isn't until after he proposes marriage that he learns she's from one of the most powerful families in Japan. Later, he starts working for his father-in-law's conglomerate, happy with his new life.
Years later, Saburo is asked by his father-in-law to attend the funeral of a man killed in a hit-and-run. At the funeral he meets the victim's daughter (Kyoko Fukada), who is suspicious of the way her father died. Saburo is drawn into a situation he doesn't understand.