Teenage Mutant Ninja Turtles.

A popular children's television cartoon series screened from 1988 to 1995. The characters were four turtles named Michelangelo, Raphael, Leonardo and Donatello, who with the aid of a ninja mask, as worn by Japanese ninjutsu, became swift martial arts experts. They were ‘mutant’ because when accidentally dropped down the New York sewer system they grew to human size and gained the power of speech. They were conceived in 1983 by Kevin Eastman and Peter Laird as a parody of the Japanese samurai-style heroes then prominent in comic strips. When they were launched in Britain ‘ninja’ was altered to ‘hero’, because it was feared British children would be baffled by the word ‘ninja’.