La porta dei mondi

Zagor and Chico receive a visit from Professor Verybad. A mysterious metal sphere, found among the debris of a flood, is displayed as a local curiosity in the saloon of Shelford, a distant village of Darkwood. From second-hand news, the professor thinks that the mysterious object may have the same origin as the monstrous alien contraption found buried in the Gray Mountains, during a dramatic event that saw them all involved together, years earlier. Verybad intends to go to Shelford to make sure that it is nothing of the sort and asks Zagor to accompany him. Meanwhile, however, someone else is also interested in the singular discovery... and monstrous apparitions make their appearance... On the trail of the thieves of the mysterious metal sphere of unknown origins, Zagor, Chico and Professor Verybad reach the home of the wealthy David Housman, on the shores of Black Lake. Housman had his men steal the sphere, to add it to his collection of objects related to esotericism and the occult, but his gesture is about to unleash unimaginable forces. And while the lakeside villa finds itself besieged by monstrous creatures from another world, Zagor must travel beyond the limits of space to prevent hell from breaking loose on earth.