The Berger family lives on the sixth and top floor of a Parisian building. They feel so good there that they would like to expand their space and dream of taking over the very nice apartment of the Tissandier family, their friendly neighbors on the fifth floor, in order to create a lovely duplex that matches their ambitions. However, the Tissandier family is happy in their apartment and has no intention of moving at all. What can the Berger family do then? They are left with only one solution: to use all possible means to achieve their goals, even the most questionable and especially the most unlikely...