In 1959, he became director and directed his first feature film, Gokigen musume. In 1962, Kengo directed Nippon musekinin jidai, which became a popular classic comedy film and since then, he produced many films for entertainment movies such as the . In 1970, Kengo left Toho and was planning to make a "Storm Over Asia" that depicts the modern history of Japan, but it never happened. 