In the Golden Age of the 1930s and 1940s, comics were mostly episodic tales in which characters barely changed. A costume might occasionally change, an origin story might be amended, a power might be granted, or a vehicle or sidekick added, but all such changes merely established a new episodic status quo. Villains changed looks, equipment, or M.O.s often without notice. Characters rarely interacted with one another, despite being owned by the same company. Even All-Star Comics, which had DC’s characters its less popular titles team up to form the Justice Society, initially did not feature the characters together and then — when it did — split the characters up for separate chapters, typically illustrated by the artists that illustrated the characters’ stories in their own titles.

The 1950s brought increasing reference to past adventures, but it was really in the 1960s that the cult of continuity took off. Characters increasingly interacted with one another, increasingly exploring the idea that they inhabited a shared “universe.” At DC, this reached its apex in the notion of multiple earths, which placed a version of DC’s Golden Age characters on an alternate earth. This brilliant move, at least ideally, allowed the older version of characters to continue to live, even continuing — or beginning — to change on occasion. This formalization of increasingly numerous parallel universes also allowed characters from purchased companies to be placed in their own universes, explaining their historical absence from DC’s own universe.

The notion of continuity became central to Marvel Comics’s famous return to super-heroes and its revitalization in the 1960s. Eschewing DC’s multiple earths, Marvel’s new super-hero line established continuity with its 1940s incarnation (when Marvel was called Timely), primarily through the resurrection of Captain America in The Avengers #4 (cover-dated March 1964). Moreover, the notion of a shared universe was deeply inscribed in the Marvel line. The fact that most of Marvel’s characters inhabited New York City both complicated this — making one wonder what Spider-Man was doing when Galactus invaded the city — and facilitated this — allowing characters to run into each other with some frequency (engendering many melodramatic hero-on-hero battles).

Marvel also created the notion of the no-prize in its letter columns. Readers wrote in to point out continuity errors — like those in film except complicated by having years of histories of intersecting characters with established dress codes — and then explain them away. The notion, supposedly comic, was that Marvel made no mistakes: any such gaffs were secretly communicative of meaning, and it was left to the readership to figure it out — to turn mistake into unstated meaning. Successful attempts at doing so were awarded with a no-prize — supposedly nothing at all, save mention in a letter column.

In the 1970s, continuity became even more formalized as stories routinely stretched over multiple issues, with increasing amounts of subplots. What became known as the Levitz Method (because it was formalized by Paul Levitz, writer and subsequent administrator at DC Comics) became prominent in this time: an issue would have an A-plot (or the main plot), a few pages of B-plot (or the subplot), and perhaps even a C-plot (a sub-subplot, given perhaps a page or half-page). The same device would become prominent in television, with each episode having an A-plot and a B-plot, typically a more masculine, action-oriented plot and a more feminine, romantic-oriented plot: thus, the police both investigated a murder and experienced troubles in their relationships. The idea was to appeal to everybody, widening the show’s audience. In comics, the Levitz Method worked thusly: a hero would battle his nemesis (the A-plot) while a few pages would be devoted to a mounting alien invasion (the B-plot) and a half-page or so would be devoted to setting up a future plot, say someone’s strange behavior. Whenever the A-plot ended, whether after one issue or five, the last page would feature the B-plot raised to the fore; beginning next issue, the B-plot would become the A-plot, the C-plot would become the B-plot, and a new C-plot would (ideally) be introduced. Thus the nemesis is defeated, and the aliens actually attack; while dealing with the alien invasion, it becomes clear that the strange behavior seen for issues is actually the result of mind control run by a new villain — at the same time, our hero’s love interest begins investigating his secret identity. As the alien invasion is defeated, the mind-controlling villain takes center stage and the love interest becomes the B-plot, with a few more pages, while a new C-plot is introduced. Following the defeat of the mind-controlling villain, the love interest confronts our hero about his identity, leading into the next issue, in which the C-plot again becomes the B-plot and a new C-plot is added. Et cetera, et cetera, et cetera. The idea — while certainly naïve — was to replicate real life, with multiple concerns running at the same time. Admittedly, this is only the ideal description of this pattern: often a C-plot or even a B-plot would be dropped for an issue or so, and sometimes a C-plot would not be used at all, or a new C-plot would not be immediately introduced, or all plots would coalesce in a writer’s final stories before he left the series. But the general pattern became increasingly popular, making each title less episodic — and more, well, soap operatic.

One can easily see a major downside to such a narrative structure: following it took some effort, discouraging new readers who had to contend not with jumping into the midst of a single story but into the midst of two or three. Indeed, continuity in general had the same effect: a villain could not appear without reference to his condition when he was last seen, if not a long continuity of his life and confrontations with the hero. As these continuities of each character became increasingly complex, involving a long trail of such abstract narrative bends as clones and parallel worlds, often with each bend written by a different writer and expressing different sensibilities, continuity became a bit of a problem.

This was never more true than at DC, which by the 1980s had forty-some years of ongoing stories, complete with continuing parallel universes. One character who was part of the main universe might have gone to another universe for some time, serious events in his life occurred there, and finally returned — only for writers to have to explain to readers not only this character’s history but who were the characters surrounding him — many of whom looked quite similar to other, more familiar characters — during those life-altering experiences on a parallel world. Moreover, numerous incompatible futures had been shown: mutated nuclear deserts were followed a couple centuries later by utopian societies and the like.

DC elected to reboot the machine, as it were. The twelve-issue mini-series entitled Crisis on Infinite Earths was to foreground these changes, killing off characters and all multiple earths, concluding with time being altered from the Big Bang itself, allowing for a single, unified continuity. Of course, this continuity became problematic even at its very inception: any character’s story was in doubt. While some characters (such as Superman or Wonder Woman) were rebooted, their stories told anew, other characters (such as Batman or Flash) were not. When Jack Kirby’s Fourth World first appeared in what became known as post-Crisis continuity, the planet Genesis (good sister planet to the evil Apokolips) was destroyed, reflecting Kirby’s Hunger Dogs graphic novel — which was shortly thereafter designated as not having happened. Worse, the Legion of Super-Heroes, living in the 30th Century, had not been affected by the Crisis event, yet had frequently worked not only with characters in their pre-Crisis forms but with characters, such as Superboy and Supergirl, who no longer existed — or had ever existed. To solve this, the villain the Time Trapper was radically escalated in terms of his power: the post-Crisis past with which the Legion had been interacting from its inception was now — and had always been — a “pocket universe” created by the villain. Ironically, all the pre-Crisis events that had been negated by the Crisis still had a kind of substance in this “pocket universe,” which was put to the torch almost as soon as it was revealed.

Worse, many minor characters without their own titles — or long-lived ones — did not get the kind of attention necessary to create a consistent post-Crisis continuity. Hawkman, in particular, was a disaster. In the early 1990s, DC attempted to rectify this problem with a second Crisis of less scope and importance: named Zero Hour, this five-part weekly mini-series featured another universe-ending and universe-recreating cosmic event. Improving on Crisis in at least one respect, Zero Hour concluded with a fold-out timeline of the slightly revised continuity. The event was used to reboot the complex continuity of the 30th Century, giving the Legion of Super-Heroes a chance to start from the beginning as Superman and Wonder Woman had after Crisis.

In the wake of Crisis, the term “retcon” was coined, short for “retroactive continuity.” Strictly speaking, a retcon refers only to the modification of past events – Crisis being a prime example. Thus, History of the DC Universe — a two-part mini-series that followed Crisis and attempted, in broad strokes, to tell the history of the new single world produced by that literally earth-shattering mini-series — provided a guide to a “reconned” universe. The term has expanded to include less world-altering events, such a character who reappears complete with a narration of his past that diverges from established history.

Marvel, ironically given its championship of continuity in the 1960s, has become the sloppiest of the two main companies in terms of continuity. Never having had the benefit of a reboot, and inevitably featuring a string of parallel universes with less of an ordering principle governing them than DC’s parallel earths, albeit less traveled and thus less confusing in Marvel’s continuity, Marvel is in serious need of a revamp. Given the choice to ignore continuity or bog new readers down in its overwhelming complexity, Marvel has chosen to ignore continuity more often than DC did. Marvel’s solution was not to reboot certain titles but to create, beginning in 2000, new titles set in a new universe, introducing characters for the first time there. Called the Ultimate universe, its characters were introduced amidst contemporary culture rather than in the 1960s that defined so many of their characters’ original versions and, to this day, their origins. Marvel has carefully controlled this enormously popular universe’s expansion, avoiding the chaos that often results in gross continuity errors. Although rumors have circulated that Marvel intends to phase out its original universe, Marvel clearly has no such plans, as many titles in its main universe still sell well.

One of the biggest inherent problems in continuity is the advancement of time. Characters simply do not age a year for every year of publication, though Christmases and yearly events come more regularly. Moreover, contemporary events and situations find reference. Many titles refer to events from a year or so before as having occurred a year or so before. This creates a strange effect: recent issues take place more or less in real time, but time becomes increasingly compressed the further back one goes. As time passes, once-recent issues increasingly become subject to this compression as well. In other words, an implicit retcon to the timeline of the narrative(s) occurs continuously. Moreover, interaction between titles aggravates this problem: following a crossover, one character’s storyline might consume months of time within the narrative while another character’s might consume just days, though both have had the same number of months of publication between them. When these characters participate in another crossover, the time between the two crossovers might be months for one character and his supporting cast but weeks for another set of characters.

The case of Zero Hour illustrates this rather clearly. The admirable timeline included in its concluding chapter measured the narrative time from the emergence of Superman and other DC heroes to the present at ten years. Obviously, this meant that stories in which computers were new occurred just a few years prior to stories in which computers were commonplace. Certain characters had experienced multiple occurrences of the same yearly holidays and of their birthdays between events that were fixed as occurring one year apart. Moreover, the ten-year timespan was measured not by historical dates but relative to the present moment: thus, Superman’s emergence in 1995 occurred in 1985 and in 2000 occurred in 1990 — which certainly feels ridiculous. Even in the year following Zero Hour, different titles depicted the passing of time differently: Wonder Woman, then engaged in a battle for her very name, had one issue continue immediately following the previous one for some time, whereas months passed for other characters, such as Starman.

I hasten to point out that such problems are not limited to DC, however: Marvel has not even bothered to fix its continuity historically, and by all indications its radical compression of narrative time is even more severe than DC’s, despite its many references in its narratives to then-contemporary events. Whereas Captain America was frozen in ice in the ending days of World War II, he was thawed in the 1960s. Since only a decade or less of narrative time has passed since those 1960s stories (in which Captain America barely ages), and since World War II is an historically fixed event, Captain America’s suspended animation continues to grow. If Marvel does not ask us to imagine Captain America frozen for fifty years instead of twenty, revived sometime in the 1990s, it is not because Marvel is superior to DC but because Marvel, while feigning at continuity, does take the severe steps that DC has taken and that would necessarily challenge the company’s readers.

None of these points is completely unprecedented. We may be inclined to dismiss comic book readers as foolish to tolerate such a situation, relying upon the old notion that children read comics and that, consequently, comics readership changes entirely ever few years as readers grow out of their addiction to four-color fantasies of flying men in capes. Of course, none of this is true if it ever was. The average comic book reader is now in his twenties, and that figure climbs every year as comic books grow increasingly a cultish, insular world dominated by special shops with an aging readership and relatively few new readers. Even in the 1960s, however, the institution of the no-prize demonstrates the savvy nature of comic book readers even at a time when comics were decidedly juvenile.

One of the most prominent aspects of the Silver Age was its imagination — the lack of self-censoring of outrageous and often clever or crazy ideas that dominated 1960s comics. Even if the readers were largely children, those children were invited to use their minds creatively, to imagine shrunken cities or universes and bizarre transformations on a regular basis. That same readership was invited to imagine creative solutions to continuity gaffs, thus pulling the readers into the very construction of the narrative universe itself.

In a sense, this is not so different from readers who spot continuity errors in movies or novels. But while the Internet Movie Datebase is full of reader comments of prideful discoveries of continuity errors in films, those contributors do not attempt to derive creative explanations as to why a character’s clothes changed between shots or his burning cigarette gets short, then long, then short again. So too with those who read novels, who do not feel compelled to explain away such errors in Charles Dickens, who produced his often masterful novels on a serialized basis similar to the production of comic books. Moreover, the deep institutionalization of continuity in American comics, grounded in ongoing interlocking narratives spread through dozens of monthly publications, has no parallel elsewhere.

The problems of continuity are often regarded as the consequences of this phenomenon of quickly-produced interlocking narratives occurring in the same narrative universe and running, in the case of both DC and Marvel, since the late 1930s. It is as if every network’s soap operas occurred in the same world, with characters meeting each other and events in one soap opera affecting events in others. Viewers would go mad. While the phenomenon of continuity is certainly an epiphenomenon of sequential production of multiple continuing narratives occurring in a shared universe, even the problems inherent in this phenomenon have a sort of genius to them.

Indeed, one of the most attractive elements of American comic books is the sheer length and complexity of their worlds’ narratives, running untold thousands of pages for any continuing character and running untold millions of pages for either the DC or the Marvel universe. At twenty-two new pages an issue, a single monthly title produces 264 pages of narrative per year or 2640 pages per decade. Of course, characters like the X-Men, Batman, Spider-Man, and Superman have many titles, and a company might produce anywhere from a dozen titles to several dozen set in the same world. Of course, length of issues and frequency of publication varies and has varied over the years. Part of the charm of these shared universes is the sheer bulk of their narratives, and even the fact that one cannot read them due to their fracture into so many different titles in any single coherent fashion. The very unfathomable and unwieldy nature of continuity, which would never be produced by the design of a single author, can also be a strength.

Indeed, the system of comics continuity, at least for companies with interlocking narratives, requires constant mental footwork. Juggling minor continuity gaffs is really the least sophisticated of such endeavors. Reading such narratives requires mentally juggling not only several interlocking and lengthy narrative lives, but constantly altering those narrative lines as they recede from the present. As one reads a story from the 1960s, one reads a tale so thoroughly ’60s in tone, even if hippies are not running around, as to render impossible imagining it in a different context. Yet, one must also read the story from the perspective of present continuity, in which that story might have occurred just a decade prior. While one cannot imagine the rhetoric and setting of the story replaced with that of the 1990s, one might extract the essentials of the story and imagine that kernel of narrative as occurring in the 1990s along a given narrative line. Sometimes, this requires imagining that a character in that story was not actually who he was, or that his actions were taken by another character, or that the same character was actually dressed differently or actually insane at the time. I would like to suggest that these are highly complex mental acrobatics — ratiocinations due great praise — and that comics continuity requires them on a regular basis.

The experience is not unlike watching classic Star Trek episodes and imagining that the technology which looks like cardboard boxes with ridiculously insignificant flashing lights is actually more advanced that the technology shown on Enterprise, which occurs earlier, or that the Klingons look like the Klingons seen on Star Trek: The Next Generation and later shows. Such an experience is like the normal continuity gaff of a cup of coffee moving between shots, only taken to a deeper level. In comics, however, the experience is more comparable to all of the Star Trek shows running and occurring simultaneously, with the Klingons and technology still looking different in one of them, then starting before it did and continuing to run without cancellation to the present day, the casts barely aging though years pass in terms of story. Watching an old episode of Star Trek, outside of being an historical curiosity, would thus become a potentially mind-boggling experience.

The astounding complexity of continuity within the DC and Marvel universes is surely not utterly deliberate. It is a product of the material circumstances of production, of ongoing stories, of interlocking narratives, of the collaboration and changes of writers implicit in such production. Yet it also requires, for an increasingly adult and literary audience, phenomenal faculties in order to process. Casual readers might enjoy particular stories without knowing of this elaborate metastructure, yet scholars of varying levels of formality and training increasingly engage in study of this metastructure, and that study entails great mental faculties.

As a case in point, one might consider Kurt Busiek’s writing of Marvels. To write his four stories of that seminal mini-series, Busiek, an expert on comics continuity, scoured Marvel’s back issues in order to retell stories from its history as experienced by the man on the ground. In order to accomplish this, Busiek had to create intersections between ongoing narratives occurring in a shared universe. As his notes to that series, published in the trade paperback collection, demonstrate, this meant determining where an event in one title fell within the events of others. Inevitably, this yields interesting results: the Avengers, for example, were engaged in a long series of stories that continued into each other, without breaks, when they guest-starred in Fantastic Four, yet the members of the Avengers at the beginning and conclusion of that long series of stories were different than during their appearance in Fantastic Four, requiring that that appearance occurred during a particular issue. Finding such a possible gap itself entails considerable mental acrobatics, but Busiek — while he largely avoided the issue of the aged historical setting of such stories (a difficult process itself, even if less than the alternative) — went a step further. Inevitably, these interlocking narratives comment upon each other: there was a historical context to the Avengers’ appearance; they had just finished dealing with a particular threat that involved particular issues when they encountered others in another title, inevitably producing thematic and meaningful resonance.

However unintended, the invitation to address the continuity of corporate super-hero meta-narratives, seen in everything from the no-prize to Zero Hour‘s timeline (and its successors as well as its immediate post-Crisis predecessor, History of the DC Universe, if not Crisis and the institution of multiple earths itself), has the effect of training readers’ interpretive imagination on a thoroughly advanced level. This is a sort of meta-version of the mystery narrative that invites readers to attempt to solve the mystery over the course of the narrative. DC in particular incorporated puzzles into their narratives, a more recent version of which might be the Marvel issue of Transformers (#41, cover dated June 1988) in which a name was scrawled in the vague spaces of the issue’s artwork over and over again, challenging readers to examine the art and find such references — not unlike Hirschfeld’s similar routine incorporation in his exaggerated, stylistic, and beautiful commercial artwork. DC’s use in the 1960s of splash pages — first pages depicting some dramatic scenario the titular hero would face during the course of the story, in fact produced prior to that story — may be seen in this context as a kind of puzzle. Indeed, the institution of continuity, as demonstrated by the no-prize, might be seen as an astoundingly elaborate and ultimately unknowable puzzle. We might surrender the challenge of solving it, recognizing its accidental nature, but we must not ignore its remarkable ability to implicitly challenge readers to identify complex narratological problems and derive creative solutions.

With the passing of time, the notion of interlocking the various narratives of titles with a single publisher has become increasingly untenable so long as those narratives remain ongoing and ever set in the present. On the other hand, this phenomenon of sprawling continuity offers a challenging puzzle and allows the reading of a single historical story not only on multiple levels but as intrinsically producing multiple revised versions of itself. I dare write that few acclaimed academics can claim such ability, and that such inclination and skill provides excellent training not only for deriving brilliant literary arguments but for identifying and solving nagging philosophical and even scientific quandaries. Moreover, such reading, as indicated by the institution of the no-prize, is invited by the stories and their sprawling context themselves. Readers ultimately are called to rewrite narratives even as they read them, to participate in the creation of a massive universe of ever-changing narrative lines shared not only between fictional characters but with readers as well.

Such is the process of interpreting history itself, ever in the process of being rewritten to create lines to the present; what is “he never loved me” but a convenient retcon? Though we as comic book readers are often superficially aware of the strange notion of continuity, we are rarely aware of the profound implications of this half-accidental institution.