Sequel to Eon (1985), exceedingly hard to follow if you haven't read the original or don't recall precisely what occurred therein. For openers, various factions are debating whether or not to reopen the Way, the endless corridor that threads through spacetime and yields doorways to countless probability worlds. The benefits are obvious: contact and trade with other inhabited worlds. The drawback: the hostile alien Jarts have probably reoccupied the corridor. Meanwhile, Way policeman Olmy discovers a Jart, captured five hundred years previously, its mentality stored in a computer and then deeply hidden. In order to study the enemy, Olmy secretly takes the Jark mentality into his own implant-enhanced brain. Then, to everyone's astonished disbelief, Mirsky shows up--he vanished down the corridor a while back, and the Way has since been closed! What's going on? Well, Mirsky turns out to be an avatar of a godlike being, the Final Mind, that exists at the end of time; the Way must be destroyed or the Final Mind cannot come into existence. Nevertheless, the Way is reopened and is found to be full of Jarts; Olmy's Jart takes Olmy over; finally, Mirsky prevails upon the Way's builder to destroy his creation, and the Jarts turn out to be allies of a sort. Imaginative but overcomplicated, bogged down in purposeless information and irrelevant subplots, largely devoid of narrative tension. Another disappointment: the ideas are there, the discipline isn't.