Martha and Helene Weiß - one a devout nun in a Swabian convent, the other a convinced atheist and mother. Two unequal sisters who almost only argue with each other. Especially Martha's faith is always a red rag for the younger and wilder Helene. But then Helene has a car accident with her daughter and husband. But when she wakes up in hospital and learns that husband and child are dead, she feels no grief. She suffers from retrograde amnesia. This means that she can remember Pippi Longstocking, for example, but not her own family. Now it is Martha, of all people, who brings her to the convent and gives her support. But can she really trust this stranger? "Sister White" is a warm-hearted tragicomedy in Swabian dialect about death, doubts of faith and trust. After his award-winning cinema debut "Sascha", this is Dennis Todorović's second feature film. The leading roles are played by Željka Preksavec as Martha, Lisa Martinek as Helene and Beatrice Richter as Helene's mother-in-law Dolores.