Monument to Giordano Bruno in Rome. (Creative Commons 4.0 photo by RuprechtN, more information here.)
If you are familiar with the work of Robert Anton Wilson, you are probably familiar with the name Giordano Bruno (1548-1600), who espoused many interesting ideas until he was killed by the Inquisition. But I did not know there is a series of well-reviewed thrillers starring Bruno as the main character, by S. J. Parris, until Nick Helweg-Larsen sent me this book review from the Guardian. (The latest book also mentions John Dee).
S .J. Parris is a pen name for Stephanie Merritt, here is the official website.