Cohabitation is difficult when an entire class ends up living in an apartment. This is what happens in this episode of "The 3C Boys," in which Chicco, having to put up for a few days an American friend who announced her arrival via telegram, finds an elegant place with a steep rent. The price forces him to involve first Massimo and then his classmates in the idea. When the American girl moves into her new "nest," numerous subtenants arrive, determined to take immediate possession of the apartment. Amid furious arguments and progressive destruction, the failed attempt at "cohabitation" unfolds. With the kids leaving, one by one, only the American friend remains, who quickly gathers together a group of her American peers, with whom she can enjoy a wonderful vacation without paying a single dollar of rent.