Opal and Quake are planetary doublets, and when they approach their stellar primary the summer tides on the oceans of Opal are violent indeed. Since Opal is nothing but ocean, those who live on the floating rafts dread summertide with a vengeance. Quake, on the other hand, has no water. Thus, summertide produces earthquakes and volcanic action of such magnitude that it is death to stay on the surface.

Why then, wonders Max Perry, Opal’s planetary administrator, do no fewer than three individuals wish to visit Quake during its most violent period? More important, why have his superiors dispatched Hans Rebka to Opal? Rebka is a troubleshooter with a galaxy-wide reputation for getting the job done, whatever it requires. What is his job on Opal?

Darya Lang is one of those who wish to visit Quake. Professor Lang is the foremost expert on a vanished alien race known as the Builders. Such is also the case with Atvar H’sial and Louis Nenda, although neither is as well-known as Darya. Nevertheless, all three have come to the same conclusion: Something is going to happen on Quake during summertide which may answer many questions concerning the Builders. Thus, each of them needs to be present--regardless of the risk. That determination conflicts with the agendas of Perry and Rebka, who also must deal with another prospective visitor, Councilor Julius Graves. Councilor Graves’s ostensible purpose in visiting Quake is to look for two young women charged with genocide.

SUMMERTIDE is identified as “Book One of The Heritage Universe.” The close of the work finds Rebka and Lang, with some rather bizarre companions, headed off into the galaxy in pursuit of they are not exactly sure what. Charles Sheffield is quite adept at sustaining multiple story lines. Moreover, he reveals information concerning his version of the universe gradually and yet in such a manner that the reader is not presented with an encyclopedia. SUMMERTIDE is the closest thing to Dune in a long time. May Charles Sheffield prosper!