Il segreto delle Ombre Diafane

A mysterious individual shows up at no. 3 of Washington Mews: he is Java's brother, who came to the so-called civilized world to seek help. Martin Mystère and Java therefore return to the City of Diaphanous Shadows, where the tribe of Neanderthals who survived the extinction live. After many years, however, things have changed somewhat and the city is in the hands of a man determined to exploit its secrets for his own benefit...