This volume contains all three novels of George Allan England's Darkness and Dawn Series:

The Last New Yorkers:

In the decade following its completion in 1909, New York's once-tallest building, the Metropolitan Life Insurance Tower, suffered a series of unfortunate mishaps. In rapid succession it was exposed to poisonous gases, submerged under twenty thousand feet of water, struck by the tail of a comet, and transported back in time to the pre-Columbian era. Each time, the building somehow emerged intact.

Beyond the Great Oblivion:

Second in the series, picks up almost directly after the first book leaves off. This time, we learn that the dynamic duo are not the sole survivors of the presumably global catastrophe.Bernice and Allan, continue in book two of the trilogy, to try to make a new world out of the old dead one, after defeating, at least for a time, the horde of primitive beasts.

They travel west in the hope of finding intelligent life and an answer.

They find at the Great Oblivion, what has happened to the Earth some 10's of thousands of years ago.

They find the descendants of past mankind, living underground, but although these people are not near beasts, they have reverted to a simple, non technical life.

How can Bernice and Allan try to repopulate the Earth with such people?

Is the afterglow of a bright new world, beyond their reach?

The Afterglow:

Bernice and Allan, end the trilogy, in this third book,

with a huge job before them, after finding and gaining the trust

of the ancestral survivors of past humanity, at the Great Oblivion.

They must take a race of underground dwellers. living in the dark, and teach them to live in the Sun of a new Earth.

But, they are still pursued by old antagonists.

Will the struggle end in defeat, or will the Last New Yorker's, after overcomming the Great Oblivion, bask in the afterglow of victory for themselves and mankind's future?