"You have to think about whether they're really your friends," Johnny's dad says when Johnny talks to him about the grief his pals have been giving him lately. The other boys haven't exactly tried to understand why Dad opened up his family's home to Miyeko, a survivor of the Hiroshima Atomic bomb. Although she is only in America a short time to have surgery on her badly scarred face and arm, her visit reveals just how many ignorant and intolerant attitudes still exist 10 years after the war's end. But Johnny, who also resents Miyeko at first, becomes one of her fiercest defenders after he makes the effort to look past her outward appearance. Only then can the scars begin to heal.
The four turtles travel back in time to the days of the legendary and deadly samurai in ancient Japan, where they train to perfect the art of becoming one. The turtles also assist a small village in an uprising.
After his family is killed in Japan by ninjas, Cho and his son Kane come to America to start a new life. He opens a doll shop but is unwittingly importing heroin in the dolls. When he finds out that his friend has betrayed him, Cho must prepare for the greatest battle he has ever been involved in.
When a western Pennsylvania auto plant is acquired by a Japanese company, brokering auto worker Hunt Stevenson faces the tricky challenge of mediating the assimilation of two clashing corporate cultures. At one end is the Japanese plant manager and the sycophant who is angling for his position. At the other, a number of disgruntled long-time union members struggle with the new exigencies of Japanese quality control.
Two New York cops get involved in a gang war between members of the Yakuza, the Japanese Mafia. They arrest one of their killers and are ordered to escort him back to Japan. However, in Japan he manages to escape, and as they try to track him down, they get deeper and deeper into the Japanese Mafia scene and they have to learn that they can only win by playing the game—the Japanese way.
Starts off in the 15th century, with Connor McLeod training with another immortal swordsman, the Japanese sorcerer Nakano. When an evil immortal named Kane kills the old wizard, the resulting battle leaves him buried in an underground cave. When Kane resurfaces in the 20th century to create havoc, it's up to McLeod to stop him.