The Third Musketeer (1965)

The fairy tale of "Cinderella" is combined with the classic adventure of "The Three Musketeers." Sad Cat wants to be a musketeer like his two older brothers. A fairy godmother appears, and he gets his wish. Jealousy splits the three, though, and Sad Cat is happy to return to being himself.

Unfortunately the movie The Third Musketeer is not yet available on HBO Max.