Crusty German character actress, the daughter of a Prussian officer and a Dutch stage actress. She made her theatrical debut in Berlin at the age of fifteen in 1878. Performed in Vienna between 1889 and 1895, at the same time romantically linked to playwright Arthur Schnitzler. Ensemble member of the Deutsches Theater, 1905-1910. She was basically a tragedienne, even essaying male roles (eg. Hamlet). Sandrock entered films well into middle age and was one of the most prolific actresses from the mid-1920's, up until her death. She specialised in despotic or imperious matrons, aristocrats, aunts, mothers-in-law or henpecking wives. Sandrock never married, living in Berlin with her older sister.