Once it was a fannish hobby to compile lists and biographies of comics characters, but increasingly not only comics companies but mainstream publishers have been producing encyclopedias chronicling comic book continuity. Usually such books deal with superheroes, but The Vertigo Encyclopedia (DK Publishing, $30) is a compendium of information about DC Comics’ acclaimed imprint dealing in supernatural fantasy and other genres for sophisticated readers.

Dorling Kindersley, or DK for short, has a characteristic method of combining illustrations and text to create visual guides to everything from tourist destinations to pop culture mythologies. Unsurprisingly, The Vertigo Encyclopediais a strikingly handsome retrospective of the work of Vertigo’s many talented artists, as well as a catalogue of its characters and series.

Here I must engage in full disclosure: I have done freelance work on several of DK’s books about comics, as well as comics encyclopedias for other publishers. So I know how monumental a task researching such books can be, and salute The Vertigo Encyclopedia’s author Alex Irvine, who, oddly, is credited on the cover but not on the book’s title page.

At least in the past, DK’s guides to comics characters like Batman and the X-Men were officially part of its Children’s Books division. The Vertigo Encyclopedia is most definitely not for kids: leafing through the book, I came across not only the F-word, but also an example of full frontal nudity and a reference to “pansexuality.” Irvine also takes a more sophisticated approach to the material, listing the credits of Vertigo creators, outlining major storylines, and even pointing out literary themes.

The Vertigo Encyclopedia impressively showcases the vastness and variety of the Vertigo line over the fifteen years of its existence. As one would expect, many pages of the book are devoted to Vertigo’s most famous series, like Sandman, Swamp Thing, Preacher, 100 Bullets, Fables, and Y the Last Man. But eighty-four different series receive their own sections of the book, and even well-read comics aficionados are likely to find Vertigo series here that they’d never noticed before. If not in the main body of the encyclopedia, then certainly they will find surprises in the Gazetteer section in the back, an appendix containing brief illustrated entries on another hundred and twenty-six Vertigo series and one-shots!

Devoted Vertigo readers will turn to this book to refresh their memories about characters and storylines they have encountered in the past. But this encyclopedia will also prove rewarding to newcomers to “mature” comics. As Vertigo founding editor Karen Berger notes in her introduction, the Vertigo line began with merely six core titles. But by now, the casual comics reader who wants to explore the line further can no longer easily survey the entire Vertigo line, which includes hundreds of one-shots and series, many of which have spawned long lines of trade paperbacks. Now a newcomer can page through The Vertigo Encyclopedia, get a sense of what different Vertigo titles are like and who their characters are, and decide which books he or she wishes to try reading.

Even before the late Mark Gruenwald created the original Official Handbook of the Marvel Universe, the pioneer of comics encyclopedias was Michael Fleisher, whom comics readers perhaps know best as a writer for The Spectre and Jonah Hex In the 1970s Fleisher embarked on the ambitious project of single-handedly writing a multi-volume Encyclopedia of Comic Book Heroes, but only three were published, on Batman, Superman and Wonder Woman. Masterfully researched and perceptively written, Fleisher’s books set high standards for the comics encyclopedia writers who followed. Recently DC Comics has republished all three of Fleisher’s encyclopedias, but though they remain the definitive guides to DC’s Big Three in the Golden and Silver Ages, these books are now, of course, three decades out of date.

The problem has been solved by The Essential Batman Encyclopedia (Ballantine Books, $29.95), written by Robert Greenberger, who was formerly DC Comics’ longtime “continuity cop.” This new book follows the format and style of the Fleisher original, covering Batman history from 1938 through most of 2007, and Greenberger has clearly undertaken exhaustive research that lives up to the standards Fleisher established. As a comics historian, I am awed by the scope of Greenberger’s achievement in this book.

One might have expected that Greenberger would emphasize more recent Batman history over the past. But no, to his credit, even now-obscure characters like Mirror-Man and Eivol Ekdal deservedly get their entries. Unlike The Vertigo Encyclopedia, this Batman book has more text than pictures, but the illustrations are well chosen, ranging from a crude early Bob Kane Batman to an Alex Ross photorealistic Zatanna.

When Fleisher wrote his encyclopedias in the 1970s, Batman’s continuity followed an unbroken path from 1938 onward. However, Greenberger has to contend with the fact that, starting with Crisis on Infinite Earths in 1985, DC Comics has rebooted and revised its canonical history time and again.

For example, look at Greenberger’s entry on Joe Chill, the murderer of Batman’s parents, Thomas and Martha Wayne. In the 1940s Batman finally caught up with Chill, and boldly unmasked before him. Ironically, Chill was gunned down by his own men when they learned he was responsible for Batman’s creation. But then in Batman: Year Two in 1987, Chill was instead slain by a vigilante called the Reaper. Then DC’s Zero Hour altered the past so that some unknown party killed the Waynes, not Chill. Then Infinite Crisis changed continuity again, restoring Chill as the Waynes’ killer but keeping him alive in prison. The reader of Greenberger’s book (or even this review) may well shake his head, wondering why DC couldn’t stick to one consistent story. Indeed, the original version of Chill’s fate is still the strongest.

Greenberger could have just stuck to the current canonical continuity in this encyclopedia and omitted the past variants. But he wisely includes both past and present versions of the official continuity in his entries. Thus the classic Batman stories of the "pre-Crisis” period remain just as much parts of the canon as the present day tales.

And now no Batman writer has an excuse for not researching the character’s history! For any Batman comics aficionado, fan or pro, The Essential Batman Encyclopedia is an indispensable reference work.