This novel was outstanding and introduced me to Upton Sinclair's 11 volume Lanny Budd series. Dragon's Teeth is the 3rd book of the series. Lanny Budd is a 30-something rich American living in Europe in the early 1930's. The plot revolves around the rise of Hitler in Germany and the beginning of Jewish persecution and the competing forces of socialism, facism, communism and capitalism. Lanny's sister's husband, Freddi Robbin is Jewish and Freddi's family has close connections to the Budds and their struggles in Europe create a riveting plot within the larger historical context. I rate it 5 out of 5 stars.
Here is a link to a New York Times article dated 7/22/2005 about the Lanny Budd series: