Doctor Jekill has a problem: he has a crazy desire for women, but they reject him because he is too ugly. Then he invented the "humus vitalis" with which for short periods he managed to transport his mind into the body of Dr. Giacinto Florio who works in a college for female re-education and is engaged to the beautiful Mafalda. Giacinto thus sees himself accused of having been where he does not remember and of having done things he knows nothing about. He therefore decides to hire Arguzio, a very skilled investigator and wizard of disguises, to find out the truth.
—Baldinotto da Pistoia