Shinobi No Mono (1962)

Directed By Satsuo Yamamoto

Here it is, Ninja Ground Zero.  This is the movie (later becoming a series of films) that is largely responsible for popularizing ninjas.  You may recognize one of the assassination techniques as it was later re-used in one of the James Bond movies.  Recommended for ninja fans everywhere.  It may not have the furious action of modern day action movies but you have to admire this early example of the genre.