A producer, Dave Appolon, is on the set of his newest film, “Dark Eyes,” where he thinks he has to do everything: he hires and fires, he plays the lover and the mandolin in a gypsy scene, he dances the male lead in a Spanish dance on another sound stage, he puts a singer under contract and listens to her sing, he calls for a ballet dancer who does a tap solo, and then he hosts the opening of his own film: he conducts the band, welcomes a couple who dance “Romeo and Juliet,” and dances himself with new talent after giving her a big smooch.