Russell Hobanís 1967 novel, The Mouse and His Child, crossed into that murky no-manís-land between childhood fantasy and grownup fiction. It had talking animals, but it also contained ideas about self-determination, reform and violence. Banking on the talking animals aspect, Sanrio America released an animated version of the tale in 1977.
The two title mice are actually a pair of wind-up toys, permanently joined together. When the child gets a glimpse of the bigger world outside the toy shop, the pair mount a quest to become self-winding. The journey is fraught with confusing and dangerous characters, including a spiritualist frog and a group of drunken rats. Eventually, the two mechanical mice fall into the hands of Manny Rat, a sewer-dwelling slave owner who has the power to make the pair self-winding, but only if he sees fit to do so.
The movie toned down the violence and some of the unhappiness of the original novel, but many of the highbrow ideas and surreal images remained intact. Unfortunately, these high aspirations ultimately did the film in, as lighter animated fare like The Many Adventures of Winnie the Pooh drew away the younger set. Producers Murikami-Wolf went on to much greater success a decade later with the animated Teenage Mutant Ninja Turtles.