La clé (2007)

Paulo, a seven-year-old little boy, lives alone with his mother. What complicates the matter is that his mum is an actress and is therefore often away from home. One night his baby-sitter, a very odd woman, offers him a magic key which enables to move to the other side of the red curtain. He thus discovers what his mother's job actually is and starts understanding her better, at the same time breaking his own solitude