The fourth and final book of the “Cities in Flight” series by Blish is my least favorite, though some of its story elements are unusual. The flying city of New York and its Mayor Amalfi have settled permanently on a world in the Lesser Magellanic Cloud beyond the edges of our galaxy, their long lives now devoted to farming and settling. Amalfi is unhappy, he longs for the excitement of his former nomadic life, and a new discovery provides a reason to return to it. Scientist on his world and the traveling world of He have discovered a major cosmic event is close to happening, a collision between our own universe and another one made of anti-matter that will wipe out everything we know and restart it all again. Amalfi and his scientists discover that an empire called the Web of Hercules in our galaxy is planning to influence this rebirth for their own ends, and Amalfi’s scientists want to stop them and influence the rebirth themselves. Thus, a new interstellar battle is underway with New York once again in flight to the center of the Universe. The crew are all doomed to die with the rest of that universe, but some elements of their personalities and ideologies might be allowed to survive if their plan succeeds.

While the ideas in this one are interesting, the plot is not as engaging. There’s too much talk, and some hard to believe melodrama between the characters doesn’t help much. The ending is, indeed, cosmic, but inconclusive. Still, having read the previous three books, it was fun to revisit these characters and ideas one more time.

Mildly recommended.