In a conventionalised, excessive world where people conformistly wear black, the new classmate Rosa attracts attention by bringing colour into the class. Nero fears for homogeneity and coherence, so he starts making efforts to assimilate Rosa. Rosa stands up self-confident for her identity, going on to wear coloured clothes. As Nero rans out of patience for Rosa's behavior, he plans to force Rosa to integrate against her will. When suddenly the light expires and everybody feels threatened getting lost in black, Rosa wearing colour is the needed escape. A parable about conformism and the importance of diversity in society.