This is definitely the later Hannah-Barbera material. Don't expect the animation to be as good as Tom and Jerry; this is long after they started producing television animation and it shows. It is mostly combining 2 live action actors over animation cells with animated characters. Gene Kelly is dancing as wonderful as he always has and the kid is not a bad dancer either. Throughout the film you will notice that Gene and the boy are not quite sure where the animated characters are in the shot. Very noticeable when Jack is talking above the heads of the mice. The story itself isn't that great and the musical numbers are not very memorable. I was really hoping that this would be a lost gem but I wouldn't recommend it to anyone looking for a good film that combines animation and live action.
Review of Jack and the Beanstalk
