Best remembered for his long standing portrayal of detective Kosuke Kindaichi in the 1970's, and being asked to reprise that role in 2006's Murder of the Inugami Clan, Koji Ishizaka, born Muto Heikichi, started his journey toward cinema fresh out of college with a stint as part of the Shiki Theater Company. By 1965, Ishizaka. at the age of 24, begun his film career at Toei. The following year, the actor made his debut at Toho with the 1966 movie Young Girls Are Everywhere. After the film, and a brief stint with Tokyo Eiga, Ishizaka became exclusive through contract to Shochiku studios up until 1973. Afterwards, the actor had trouble breaking back into cinema. Ishizaka's luck was about to turn around, though, when Kon Ichikawa cast him as the famous detective Kosuke Kindaichi in the 1976 production of The Inugamis. A hit at the box office, Toho brought on director Ichikawa to create another film with the character the following year called Lullaby to Kill (1977), to which Ishizaka was selected to reprise the role. Proving popular with audiences, Toho asked the pair to create three more films around the character, the last of which was House of Hanging (1979). It was from this experience that the actor would become a quick favorite of director Ichikawa, and Ishizaka would appear exclusively in his films for the six year period from 1983 to 1988, with the only exceptions being The Return of Godzilla (1984) and Oración (1988).

Acting Toho Filmography
Young Girls Are Everywhere (1966) - Shokichi Murase
Young Taro (1967)
The Inugamis (1976) - Kosuke Kindaichi
Lullaby to Kill (1977) - Kosuke Kindaichi
Hell's Gate Island (1977) - Kosuke Kindaichi
Queen Bee (1978) - Kosuke Kindaichi
House of Hanging (1979) - Kosuke Kindaichi
The Makioka Sisters (1983) - Teinosuke, Sachiko's Husband
Ohan (1984) - Kokichi
The Return of Godzilla (1984) - Power Plant Guard
The Burmese Harp (1985) - Inoue, Commander
Rokumeikan (1986) - Einosuke Shimizu
Actress (1987) - Shiro Kido
Princess from the Moon (1987) - Mikado
Tsuru (1988) - Narrator
Oración (1988) - Yoshinaga
Yawara! (1989)
47 Ronin (1994) - Yoshiyasu Yanagisawa
Sinking of Japan (2006) - Naoyuki Yamamoto, Prime Minister
Star Reformer (2006) - Hitoshi Koga
Murder of the Inugami Clan (2006) - Kosuke Kindaichi
I Want to Return to the Family (2008) - Yano, Lieutenant