David Gordon Reid and Johann Sebastian Bach have a lot in common. They are both virtuoso musicians and conductors of renown. They are both two of the greatest composers in history. David Gordon Reid, considered the first great twenty-first century composer, even looks like Bach, and like Bach, he is going blind on the debut of his new symphony. The composer's closest friend thinks someone is trying to kill him, but then he also thinks J.S. Bach was murdered, as preposterous as it sounds. Is the same thing happening all over again? Bach Again blends music and science together in a story of intrigue and suspense, to tell how an ancient oath and a family's DNA, still alive after 300 years, can change the course of musical history and what it means to be human.