Beethoven's Hair is the story of a lock of Beethoven's hair-- how it got from him to a couple Beethoven fans in the 1990s and what the hair can tell us about Beethoven himself.
The book had two things I really enjoy reading about: history and (basic) science.
The hair was cut from Beethoven after his death. This was a common practice in the era. It eventually ended up in an auction at Sotheby's and was purchased by two American collectors. The collectors tried to track the hair's path to them. Somehow it was given to a doctor in Denmark who was helping Jews escape from the Nazis, but they could only guess at who gave it to him. (I love the story of how the Danes helped the Jews escape. Pick up Number the Stars by Lois Lowery for an easy version of what happened.)
The collectors also decided to have the hair tested to try to determine what health problems Beethoven had. Their results were interesting. I think it's fascinating how science can give answers 150+ years later.
Overall, even though the book had some interesting sections, it wasn't anything I had to keep reading.