Gene Kelly was never very popular as a singer, even though he did cut records and was seen in movie roles in which he sang -- rather, it was his work onscreen as a dancer, choreographer, and director that allowed him to exert a key influence over the popularity of certain song catalogs in the mid-20th century. Showing an early aptitude in both gymnastics and dance, Eugene Curran Kelly, as he was named at birth, had devoured, by his early teens, everything he could about dance in general and ballet in particular. He was already a successful dance teacher in his hometown of Pitt...