When the dance sequence with Gene Kelly and Jerry Mouse was screened for MGM executives, someone noticed that, although Gene Kelly's reflection shone on the floor during his dancing, Jerry's did not. This required animators William Hanna, Joseph Barbera, and their team to go back and draw Jerry's reflection on the floor as he was dancing.
One of the rare occasions when Jerry Mouse actually talks.
Although many have said that a longstanding resentment between the two leads was started during this project, there is little to no evidence to suggest this. Quite the contrary, it was this film that started a lasting friendship between Frank Sinatra and Gene Kelly that spawned two other film projects.
It took Frank Sinatra eight weeks to learn the dance routine for the berthing area scene. Ultimately, it took 72 takes to get the right footage, though this was probably more due to Gene Kelly's meticulous need for perfection rather than Sinatra's inexperience as a dancer. Sinatra later said that he could have made an entire film in eight weeks.