Pentimento: A Book of Portraits is a 1973 book by American writer Lillian Hellman. It is best known for the controversy over the authenticity of a section about an anti-Nazi activist called "Julia", which was later made into the film Julia. Muriel Gardiner, a wealthy American who went to medical school in Vienna before World War II and became involved in anti-Fascist resistance there before her return to the US in 1939, suggested that her life story was fictionalized as Julia.