It is a novel about a period in the lives of Juan Lezuza and his friend Luis Obelar during the first years of the rule of Phillip IV of Spain. Juan Lezuza is appointed teacher of the King, but it is indicted of heresy for his authorship of a book explaining the mathematical foundations of the heliocentric theory.

The story is very similar to the Galileo affair, but I think it is nicely written and also exposes the political manipulation of (scientific) truth. Lezuza's wife, Inesa, is also an interesting character that invites to some reflection.