Sato left home during his high school years and entered the film department of Tama Art Academy, a vocational school attached to
Tama Art University, but dropped out after one year. and the following year he made his film debut in the movie
The Gate of Youth. When he saw this film in the movie theater and saw his own image on the screen, he made a renewed decision to live his life as an actor. and the
Blue Ribbon Award for Best Newcomer. He won the
Blue Ribbon Award for Best Actor for
KT and
Utsutsu in 2002 and
Best Supporting Actor in 2023. He is the first actor since his father,
Rentarō Mikuni, to win three
Blue Ribbon Awards for individual awards. Sato said that his encounter with the two directors was a major turning point for him. The two directors are
Shinji Sōmai, director of the 1983 film
The Catch and
Junji Sakamoto, director of the 1994 film
Tokarev. Director Somai taught him, "Sadness and anger are not one thing. Try to express your anger in ten different ways. You are not sad because you cry, but you laugh because you are sad." He and Sakamoto hit it off and became a regular actor in Sakamoto's films and appeared in many of his films, including
Face,
KT,
Children of the Dark, and
Human Trust. Debates about acting can get heated, and Sato and Sakamoto once got into a fight in a bar and were interceded by
Yoshio Harada, who was there. In 2023, Sato and his son
Kanichiro co-starred in Sakamoto's film
Okiku and the World. Sato also said that his encounter with director
Kōki Mitani opened up a new path for him. Sato took on the challenge of a full-fledged
comedy in
The Magic Hour, a 2008 film directed by Mitani, in which he had never acted before. The scene in which he plays Murata, an unsuccessful actor, comically keeps jumping on a
trampoline and licks a knife "with a bizarre look on his face" as described in the script written by Mitani was so impressive that the scene was even imitated by a
impersonator. This role, played by Sato, who had a strong image as a serious actor, became a topic of conversation, and the film led Sato to broaden his acting range into the field of
comedy. ==Arguments with the director==