"Anchors Aweigh" (1945)
When Sinatra entered films in 1943 with the tepid RKO musical "Higher and Higher," he was far from his image of the cool, ring-a-ding-ding Chairman of the Board. The idol of bobby-soxers around the world, his film persona was that of a shy, skinny, naive young man, someone you'd want to take home to meet your mom.
And that wholesome image continued when he left RKO and moved to MGM in 1944. This sparkling musical comedy, which teamed him with Gene Kelly, was his first film at the new studio. The two play a pair of sailor buddies on leave in Los Angeles who try to help a movie extra (Kathryn Grayson) become a star. The movie, shot in Technicolor, was nominated for several Oscars, including best film, lead actor (for Kelly) and song for "I Fall in Love Too Easily," which was one of Sinatra's big hits.