The documentary Urban Sea depicts the discovery of a Rio de Janeiro under the ocean, a parallel universe within the city, known only by a few who have the privilege to understand and live in this world. The film is the result of a tireless 15-year search for clean waters and to document the lives of some of these personalities who confront the ocean day in and day out. We follow the lives of 5 characters for 15 years, their relationship with the sea. The sea bed of Copacabana and Ipanema first shown in a movie.