Third in Carter's Zarkon: Lord of the Unknown series--and the idea is starting to pall. The Nemesis of Evil and Invisible Death (both 1975) had a certain museum-piece interest, with their painstaking reconstruction of the stylistic and narrative gimmicks of '30's pulp (apparently an in genre, these days). Here the Lord of the Unknown and the Omega crime-fighters pursue a weird manlike shape beneath a live volcano in the ""Luzon"" Islands, and Carter introduces a well-stacked broad by the name of Phoenicia Mulligan who is apparently scheduled to turn up in further Unknowns. A little more perfunctory than the first two. Next: The Earth-Shaker.