Their relationship lasted for more than twenty years, and she acted in productions of Weiss' dramas.

After a short stint as a wartime nurse in 1914/15 she received an education as a dancer and launched a successful career.

Her first novel Das verlorene Kind (The Lost Child) was published in 1926 and caused great controversy for its subject matter, the lust murder of a four-year-old girl by an older boy.

The book, based on a real 19th century crime case and drawing from both the genres of the detective novel and the psychological drama received rave reviews.

In 1927, Rahel Sanzara married the Jewish stock broker Walter Davidsohn, who emigrated to France to escape persecution from the Nazis, while she remained in Berlin, already weakened by cancer.