Diamond Ruby tells the compelling story of Ruby Goldstein, a Jewish boxer who rose from the streets of New York City's Lower East Side to become a celebrated figure in the 1920s and 30s boxing world. Known as "The Jewel of the Ghetto," Goldstein's life was a testament to skill and perseverance, both in the ring and later as a respected referee. This biography chronicles his journey through a vibrant and challenging era, highlighting his personal triumphs and the broader historical context of his time.