The 'philosopher' (modernist intellectual of the French 18th-century Enlightenment) Denis Diderot is part of an aristocratic circle which practices the libertarian principles on the rural castle estate of the baron of Holbach, and prints their forbidden publication, the Encyclopédie, drowning the noise of the presses in Jewish assistant Abraham's organ playing. Then arrives Madame Therbouche, a flirtatious painter, from the Prussian metropolis Berlin, and convinces Diderot to pose for her more daring then his idol fellow-philosopher Voltaire in Berlin: in the nude, leading to an animated row with his wife Antoinette, still naked except for a very unsteady sheet, all over the estate's park. Worse, the saucy scene is witnessed by a feared visitor, Holbach's brother the Cardinal, who is hunting for the illegal Encyclopaedia printers; to divert him, the baroness confesses her real and imagined sins since years and next sends in every female to do the same, later joined spontaneously by chevalier (marquis in the end credits) de Jerfeuil, who got a livelier show the he bargained for when accepting to be shown two inseparable marquis's 'sabre collection' which proves not of the military variety. The baroness also treats her guests to (then) most exotic foods and naughty pictures, yet even for her the freedman Turkish hamam eunuch Mohamed takes hospitality for female guests too far into intimate massage to their taste. His personal experience keeps changing Diderot's ideas, and therefore the article he is writing on 'morale' (morality). Secrets end up getting out, both the portraitist's true agenda and what goes on in the chapel, which the Cardinal finally gets into to 'recollect himself' after hearing so many unsettling lustful sins...