Yutaka Yoshii was too involved in the 1960s student demonstrations in Tokyo to pay much attention to the arrest of a 19-year-old youth in 1969 over four fatal shootings.

Yuji Sunaga, meanwhile, who was born 10 years after Norio Nagayama's arrest in Tokyo, for a long time knew next to nothing about the four homicides he committed between October and November 1968.

On the 15th anniversary of Nagayama's execution Aug. 1, 1997, at age 48, a group of people, including Yoshii, now 66, and Sunaga, 33, is working to spread the killer's final wish — that others wouldn't repeat his mistakes.