ZERO HOUR: CRISIS IN TIME

(See also Zero issues in 40 individual DC titles)

 5 issue Mini-Series with four numbered issues and also a zero issue. Issues came out weekly with the first issue being #4, counting down to #0.

Collected in the Zero Hour: Crisis in Time Trade paperback and the Zero Hour: Crisis in Time Hardcover collection.

Zero Hour: Crisis in Time was a crossover event that thematically followed DC's 1985 crossover event Crisis on Infinite Earths. During the Crisis on Infinite Earths, the DC multiverse was condensed down to a single universe, which necessitated a revamping of the origins of many of its superheroes.

Because of these revamps, and their delays in taking effect, DC Comics’ continuity became muddled; for instance, Superman was said to never have been Superboy, which affected the history of the Legion of Super-Heroes. The retcons caused havoc in the characters’ timelines.

DC sought to rectify this by creating a new event called Zero Hour, which would relaunch all of the heroes from the same point in time. They would use this event to make some changes (minor for the most part) to characters’ backstories, to allow for previous inconsistencies. From a marketing point-of-view, they also used this event to cancel lower-selling books, while launching new books with new origins for characters. Titles that were cancelled include Justice League International, L.E.G.I.O.N., Team Titans, and Valor.