ある日､坂本金八(武田鉄矢)は交通事故の現場に出くわす｡この事故で旧3年B組の教え子･安恵美智子(小林聡美)の母親･菊子(岩本多代)がケガをし､病院に運ばれた｡目撃者の証言から､事故原因は一方的に菊子の前方不注意と判断された｡菊子は｢目の前に男が飛び出してきた｣と主張するが､受け入れてもらえない｡

桜中学に､2年B組の市田正(斉藤喜之)の父親(山田吾一)が怒鳴り込んできた｡息子が"いじめ"にあってケガをしたと言うのだ｡学校内に"いじめ"が横行しているとは､2B担任の坂本金八(武田鉄矢)でさえ思いもよらない事だった｡正は仕返しを恐れ､相手の名前を言おうとしない｡

One day, Kinpachi Sensei receives an urgent call for help from a former student. The young man's mother is on a drunken rampage. Kinpachi succeeds in straightening things out, but on his way home he is preoccupied with thoughts of his young son, who is a student at his school. Suddenly, he is attacked by a group of middle school students...!

Kinpachi Sensei's former 3B students come together again at the one-year anniversary of former principal Mr. Onishi's death. Rikiya is upset that some of his old classmates have stood them up. He rushes over to Mikako's home to demand an explanation. When a break-in occurs in the home next door to Mikako, Rikiya becomes a suspect.

Generations of 3B students band together to assist their ailing teacher with one last task before his retirement; helping delinquent student Kageura graduate and get into high school.