Zero Hour (vol 1) #0-4 Complete Set VF

0.  ZERO HOUR PART 5

Despite the numbering, this is actually the last issue in this five-part countdown mini-series. The series should be read in reverse order, from four to zero.

Various heroes battle the godlike Parallax (Hal Jordan) and his allies in order to prevent him from recreating a new and "improved" universe. 

1. ZERO HOUR PART 4

The universe continues to unravel through time, destruction working its way to the present. In fact, cities begin to vanish, and futuristic characters such as Impulse and Booster Gold disappear. Jack Garrick appeals to The Spectre for help. Hal Jordan as Parallax--Extant's partner in cosmic crime--reveals his plan to reform and reshape the universe as he sees fit. 

2. ZERO HOUR, PART 3

The universe continues to unravel. Alan Scott and Jay Garrick retire in the wake of the annihilation of fellow Justice Society members. Various heroes battle Extant and a possessed group of Team Titans.

3. ZERO HOUR, PART 2

The universe is unraveling, destruction working its way from the future to the present and from the past to the present, and the heroes of earth gather to form a plan of action. Superman is quickly voted in as leader of the impressive gathering. Anomalies continue.

4. ZERO HOUR, PART 1

Readers of Zero Hour should read this issue first, then work their way backward to number zero. 

The universe is being destroyed by an all-consuming force that is working its way from the distant future to the past. Wally West Flash, like Barry Allen before him, tries to stop the crisis, but vanishes in the process. In addition, anomalies, such as Barbara Gordon appearing as Batgirl (despite the fact that Joker paralyzed her years before), begin popping up all over the world. 

The Flash's storyline continues in The Flash #0