Always dressed in black, Rosie casts a sardonic and offbeat eye on the world around her. And she’s never at a loss for words. Her world is confined to her house and its surroundings, where she regularly meets her neighbor, Olive, who she takes a malignant pleasure in driving up the wall. Whenever she feels the need, Rosie brings in her imaginary friend Blackie, an easy-going green sheep. A good friend, he is the only person she confides in because Blackie has the advantage of never being able to tell anyone else her secrets.