Originally published in the U.S. by Lancer as "Baron Sinister" in 1965. This Italian edition is number 174 in the (then) weekly "Segretissimo" series published by Arnoldo Mondadori Editore on 30th March 1967. Joseph Hilton Smyth, writing as Joseph Hilton, created the character of Bart Gould, but the series was continued under the byline of the House pseudonym Joseph Milton. The actual author of this instalment is not known. Cover art by Carlo Jacono.