This essay aims at probing into the dark truths and the issues in Albert Einstein’s life in Mark St. Germain’s relativity. The playwright dramatizes Einstein’s lesser-known public and private life. In the process, he does not force his viewpoint but induces readers/audiences to reevaluate his life as a whole. Einstein’s dark truth in his public life is that he made a crucial mistake of signing a letter to Franklin D. Roosevelt to develop an atomic bomb prior to Nazi Germany. Einstein’s private life discloses the dark truths in his relationships to his first wife, Mileva Einstein, and their two sons, Hans Albert Einstein and Eduard Einstein. The dark truths revealed in his private life can be summarized as his disloyalty to Mileva, his inappropriate advice or warning regarding Eduard’s career and his campus dating as well as Hans’ career and his marriage. Besides, the play dramatizes the issues on Einstein’s view of religion, Mileva’s contribution to Einstein’s scientific research, Lieserl Einstein’s whereabouts, and the controversy on Greatness vs Goodness between Einstein and Margaret Harding/Lieserl Einstein in the play. Therefore, Mark St. Germain’s relativity is adequate to get critical attention in that the play induces readers/audiences to reevaluate Einstein’s public and private life without imposing his viewpoint on them.