From the city centre to the outermost fringes of the conurbation, a two-way invasion is taking place: while urban sprawl eats into the countryside, nature is moving into the city. In a setting so completely dominated by human beings, what space is left for plants and animals? This film focuses on the tough, adaptable species that manage to survive in our towns and cities and asks if these resourceful stowaways are doomed to disappear, shedding light on a significant facet of European wildlife.