Some people find her removed from reality. Her older sister Katia even thinks she's stupid. But this is only a first impression, perhaps the result of her subconscious desire to remain a child. Or perhaps, her strange behavior is a defense against the uninspiring life she leads, a cruel existence shared with her sister and mother. Having emigrated from Russia some years previously, her mother tries to build up a life in Amsterdam and is drawn into the world of prostitution. Slowly, oldest daughter Katia follows her mother into the same obscure world. Our heroine, Katia's Sister, adores her older beautiful sister Katia, but she is getting more and more lonely, having nobody to share her feelings with. Although her surroundings are harsh, she does not judge. She continues to see the world in an unconditional and even loving manner. Despite her non-judgmental attitude, she becomes increasingly isolated, creating her own protective universe in which she sacrifices a lot, even her own name, referring to herself only as "Katia's Sister."