In the mid-nineteenth century, Gregor Mendel, a friar who taught natural science in the provincial Austro-Hungarian capital of Brunn (today Brno, Czech Republic), began to experiment with breeding garden peas. Meticulously recording his observations of their inherited traits over a number of generations, he developed the basis of the modern science of genetics. Mendel's discoveries were so far in advance of their day that it wasn't until 50 years had passed that their importance was recognised by the scientific community. Today he is recognised as one of the great scientists of history. The story of genetics, of course, did not stop with Mendel. In a fascinating account of scientific history, author Simon Mawer continues the narrative through the work of the life-scientists who built their own research on Mendel's discoveries. These include the discovery of the DNA molecule by scientists led by James Watson and Francis Crick in the early 1950s, the Human Genome Project completed in 2003, and the remarkable discoveries of geneticists that continue today.