Any corrections or observations I've missed are more than welcome; please add them to the comments! A shorter version of these notes originally appeared over at The Savage Critic(s).
Front cover: As with apparently all FC-related covers, the design here involves three vertical columns.
Title: It's worth unpacking this a little. DC is, of course, the publisher of this comic and the corporate owner of its intellectual property; DC stands for DETECTIVE COMICS, one of the first series it published, beginning in 1937. The "DC Universe"--DCU for short--is the shared setting for most of the superhero comics DC publishes, a setting that extends beyond Earth to the entirety of existence. (In fact, the DC Universe is a "multiverse," a set of parallel universes--52 of them at the moment.) And "zero" implies that this story happens "before the beginning" of the forthcoming FINAL CRISIS story. "Zero" also has two other connotations in the context of the DCU. One is that this issue was originally more or less intended to be the final issue of COUNTDOWN, a.k.a. COUNTDOWN TO FINAL CRISIS, a weekly series that began with issue 51 and counted down to issue 1--instead of its original plan of ending with issue 0. (Despite its title, COUNTDOWN actually appears to have had few direct ties to FINAL CRISIS; where they're relevant, they'll be described here.) The other is an allusion to ZERO HOUR, a 1994 five-issue miniseries about the destruction and re-creation of the DCU; the month after it ended, all DCU titles published issues numbered 0.
The character in the foreground is Superman. If you need these notes to explain that to you, they may not be much help in general.
Left column, top to bottom (-ish): Hawkman and Hawkgirl, Green Lantern (Hal Jordan), Zatanna, the Spectre (Crispus Allen), Wonder Woman, Martian Manhunter, Black Canary, Green Lantern (John Stewart), Green Arrow, Batman, the Flash (unclear which one).
Middle column: the Legion of Super-Heroes--specifically, the updated version of the first Legion seen in "Superman and the Legion of Super-Heroes," ACTION COMICS #858-863. (I'll get to an explanation of the three Legions eventually.) In the background, we see the "Superman/Legion" version of the Legion's clubhouse/HQ. Top to bottom: Dawnstar, Wildfire, Colossal Boy, Chameleon Girl, Lightning Lass, Night Girl, Invisible Kid II, Lightning Lad, Polar Boy, Shadow Lass, Timber Wolf, Saturn Girl, Phantom Girl, Sun Boy, Ultra Boy, Cosmic Boy, Shrinking Violet, Brainiac 5, Bloc (obscured by the word "Begins").
Right column: bad guys. Top to bottom, more or less: Weather Wizard, a bunch of Shadow Demons, Killer Frost, Superman Prime, Heat Wave, Giganta, Black Hand, Mirror Master, Dr. Light, Libra, Killer Croc, the Joker (in his "classic" design), Captain Cold, the Human Flame, Zoom, and (obscured by the UPC box) Professor Ivo and Dr. Poison.
It's somehow fitting that, on the first page of a multi-title arc that will apparently draw on Jack Kirby's "Fourth World" multi-title arc very heavily, we get a tribute to one of his signature artistic techniques, the extreme long shot. This page seems to have been a last-second rewrite: in the version included in the 2008 New York Comic-Con program, the caption was "I am... everything." Note also that the captions start with a black background, and that the red creeps in from the right as the story progresses.
The idea of an entity that can be everything (and articulate it!) relates to the concept Morrison has mentioned a few times of trying to make the DC universe sentient. "This is me" may refer to "everything"; it may, on the other hand, refer to the tiny little yellow lightning bolt we see between the captions, for reasons that will be clearer later. The implication of this issue is that the narrator is the second Flash, Barry Allen, who first appeared in SHOWCASE #4 in 1956. He died in CRISIS ON INFINITE EARTHS #8 in 1986.
Panel 1: Clockwise from upper left: Wonder Woman, Superman, Green Lantern (Hal Jordan), Aquaman, the Flash (from context, apparently Barry Allen), Batman, Martian Manhunter. This was the first lineup of the Justice League of America to appear in a published story, THE BRAVE AND THE BOLD #28, in 1960 (currently in print in Showcase Presents: Justice League of America, Vol. 1). They appear to be coming out of their original headquarters, a cave in Happy Harbor, RI, which also first appeared in that issue.
Panel 2: L-R: Hawkgirl, Hawkman, Green Arrow, Black Canary, the Elongated Man, Zatanna. These are all characters who later joined the Justice League of America.
In the DCU, not just the sun but the entire multiverse system revolves around the Earth. It's nice to feel important. "The barriers between parallel universes bleed": This may be a reference to "The Bleed," a transitional space outside reality often seen in WildStorm Universe comics like THE AUTHORITY--the WildStorm Universe is one of the parallel universes that are part of the DCU (specifically number 50 of 52).
"The skies drip red": this is probably a good place to mention the red-and-black symbolism that comes up a lot in this issue. Red, Morrison has occasionally suggested, represents life, specifically animal life (Animal Man is connected to the elemental force "the red," as Swamp Thing is connected to "the green"); black here appears to symbolize not quite death, as such, but "Anti-Life": total submission, futility and loss of the self.
The Anti-Life Equation was the McGuffin of Jack Kirby's "Fourth World" comics in the early '70s, the thing that the free will-despising villain Darkseid sought on Earth. We'll be coming back to this idea. "Red skies" were one of the effects of the events of the CRISIS ON INFINITE EARTHS miniseries; other comics that crossed over with COIE often had red skies visible in their backgrounds (and sometimes very little other connection to COIE).
Panel 1 is a George Pérez image from CRISIS ON INFINITE EARTHS, in the course of which the then-infinite parallel universes were telescoped into one. The big background figure is the Anti-Monitor. Small figures, clockwise from top left: the Elongated Man, Superman (of Earth-Two), Kole, Black Condor, Dr. Light II, Pariah, Captain Marvel, Aquaman, Tempest (I think), Captain Atom, Harbinger, Power Girl, Mary Marvel, Hawkman.
Panel 2 is a Phil Jimenez image from INFINITE CRISIS. Pictured: Superman Prime.
Panel 3 depicts Darkseid. We'll be seeing a lot of him, I understand.
This scene happens a thousand years in the future, the setting for most stories about the Legion of Super-Heroes.
Panel 2: The guy with the cape is, of course, Superman, created by Jerry Siegel and Joe Shuster; he first appeared in ACTION COMICS #1 in 1938, and is indeed "the last son of the planet Krypton." The guy with scarlet skin is Tyr, created by Cary Bates and the late Dave Cockrum; he first appeared in SUPERBOY #197. Tyr's name is the first direct reference to a god this issue, specifically Týr, the god of fistfights and single combat, a concept with which superhero comics of the era now ending are too familiar.
Panel 3: Superman is also Clark Kent. In recent years' comics, members of the Justice League have often referred to each other by their civilian identities' first names. At the time of Barry Allen's death, that wasn't yet the custom; hence, perhaps, the narrator's confusion ("didn't he?").
Panel 5: It wouldn't be a Geoff Johns comic without dismemberment, but at least this character's meant to be one-handed--and "hands" are going to be a running theme in this comic, so take note.
Panel 7: Followed by "we could use a hand out here." Superman is wearing a Legion flight ring on his middle finger--the custom of members of the Legion of Super-Heroes in the recent "Superman and the Legion of Super-Heroes" story. The Legion first appeared in ADVENTURE COMICS #247 as a group of super-powered teenagers from 1000 years in the future who traveled back in time to befriend Superboy (later Superman) as a teenager; their traditions of costumed heroism were inspired by Superman and his associates.
Panel 8: Brainiac 5 of the Legion of Super-Heroes, created by Jerry Siegel and Jim Mooney, who first appeared in ACTION COMICS #276.
Panel 9: The woman holding Brainiac 5's hand is the White Witch, another Legion member, created by E. Nelson Bridwell and Curt Swan, who first appeared in ADVENTURE COMICS #350. Not sure who the other woman in this scene is. There's a séance going on; the crystal ball on a pyramidal base recalls JUSTICE LEAGUE OF AMERICA #21 (from 1963), "Crisis on Earth-One"--the first "crisis on multiple Earths" story (reprinted in Crisis On Multiple Earths, Vol. 1). Merlin gave the crystal ball in question to the League in JUSTICE LEAGUE OF AMERICA #2; note that in Grant Morrison's SEVEN SOLDIERS OF VICTORY, a Merlin is an "imperishable treasure" made of living language that's given to mankind.
The shadow demons the Legionnaires are fighting first appeared in CRISIS ON INFINITE EARTHS. The scene is Superman's home city of Metropolis, a thousand years from now; the building halfway down the right side of pg. 6 is the 31st century HQ of the Daily Planet, the newspaper Clark Kent works for in the 21st century. (The holographic text circling the globe is "Daily Planet" in the future "Interlac" alphabet.) And people say newspapers are doomed! Good guys, clockwise from top left: Blok, Superman, Wildfire, Shadow Lass, Lightning Lad, Saturn Girl, Cosmic Boy, Night Girl, Sun Boy, Colossal Boy, Chameleon Girl, Polar Boy, Timber Wolf, Lightning Lass, Dawnstar.
Again with the obvious: we're seeing Batman, who was created by Bob Kane and Bill Finger, and first appeared in DETECTIVE COMICS #27, and the Joker, who was created by Jerry Robinson, Bill Finger and Bob Kane, and first appeared in BATMAN #1. The Joker is criminally insane, and in this scene he's institutionalized in Arkham Asylum.
Geoff Johns implied in a Newsarama interview that the scenes of this issue are happening in reverse chronological order; hence, the Batman/Joker scene may be set a little while in the future. [ETA: In any case, it happens before BATMAN #677.]
This scene is a callback to the opening scene of Batman: The Killing Joke, in which Batman goes to visit (a false) Joker in Arkham Asylum. And here we go with red and black again... the version of the Joker visually resembles the scarier version introduced in Morrison's BATMAN, rather than the one we've been seeing in SALVATION RUN (and on this issue's cover).
[ETA: Simon Hacking notes that "Red and black. Life and death," etc., quotes something the Joker said in BATMAN #663.]
Panel 6: The ace of clubs may refer to the Club of Heroes, recently seen in Morrison's BATMAN, and/or its counterpart the Club of Villains; it traditionally represents desire for knowledge. The eight of diamonds traditionally represents material power; as Bruce Wayne, Batman is rich and powerful.
In THE KILLING JOKE, the fake Joker of the opening scene seemed to be playing some solitaire variation of Klondike; here, the real one is just dealing cards. (In panel 4, he's doing a fancy shuffle--for a second I thought he was building a house of cards.) The Black Glove has been making mostly-offstage appearances in BATMAN recently.
Panel 6: The eight of hearts traditionally represents the decentering force of love. It's been suggested that the "Batman R.I.P." storyline this scene teases will involve Bruce Wayne giving up his Batman identity because of love. (Love, after all, does not arrive politely.) [ETA: BATMAN #677 indicates that the 8, ace, 8, ace pattern is also an alphabetical substitution cipher: H.A.H.A.]
The harlequin pattern of the joker card is echoed not just by the floor but by the layout and color scheme of the page. The sixteen-panel grid and flurry of close-ups recall the look and pace of Batman: The Dark Knight Returnsthe alternating-color panels recall Alan Moore and Dave Gibbons' non-DCU series WATCHMEN, as does the spatter of blood on the card.
Panel 1: The "dead man's hand" is two aces, two eights and something else (here, cleverly, the wild card), supposedly the hand Wild Bill Hickok was holding when he was shot. (The aces and eights are usually all black, but this fits the symbolic scheme of the scene and the issue better.) The term also recalls the Hand of Glory from the non-DCU Grant Morrison-written series THE INVISIBLES.
Panel 2: The ace of spades is traditionally known as the death card, and also represents an initiation into mysteries: "let there be light," as that link puts it. (See pg. 24.) "Hurt you so bad you'll never recover": arguably Batman's entire career proceeds from the childhood trauma of seeing his parents murdered.
Panel 5: The hand missing a finger echoes the assailant from BATMAN #675, and also suggests the name of Batman mastermind Bill Finger!
Wonder Woman, created by William Moulton Marston and Harry G. Peter, first appeared in ALL STAR COMICS #8 in 1941; here she's fighting a minotaur, this variation of which I believe was created by George Pérez and Len Wein and first appeared in WONDER WOMAN #13 in 1988.
All three dust samples are being collected from genocide sites. Wonder Woman herself was brought to life from a clay statue; perhaps something similar but more sinister is planned for this soil.
Panel 3: Professor Ivo, created by Gardner Fox and Mike Sekowsky, first appeared in THE BRAVE AND THE BOLD #30. He's the creator of the android Amazo; the android standing behind him here, though, appears to be Red Volcano, who has never appeared before but has a name analogous to Red Tornado, a Justice League member who's an android created by T.O. Morrow. (In the series 52, the existence of Red Inferno was mentioned; no water-related android has yet been mentioned.)
Dr. Poison first appeared in SENSATION COMICS #2, although the one we're dealing with is most likely her grandchild, who first appeared in WONDER WOMAN #151.
This would appear to be Zeus and Apollo; Wonder Woman is indeed Hippolyta's daughter and Athena's champion.
Barry Allen and Hal Jordan were friends. We're seeing two Green Lanterns here: John Stewart (created by Dennis O'Neil and Neal Adams; first appeared in GREEN LANTERN #87 in 1971) and Hal Jordan (created by John Broome and Gil Kane; first appeared in SHOWCASE #22 in 1959). The "Federal penitentiary" may or may not be the prison planet in SALVATION RUN; Hector Hammond, the Shark, Evil Star and Black Hand are all characters the Green Lanterns have fought. Black Hand (also created by Broome and Kane; first appeared in GREEN LANTERN #29 in 1964) lost his right hand when Hal Jordan, as the Spectre, burned it off; he's able to reconstruct it by draining people's life force. And I don't think it can be an accident that Black Hand and the Black Glove are both referred to inside of five pages.
The idea that there are a rainbow's worth of Lantern Corps was established in GREEN LANTERN #25 in 2007; that issue also included a preview of a 2009 storyline called "The Blackest Night," which (as we see in the following ad) involves someone wearing a ring whose design is the same as Black Hand's chest logo. Each corps is, more or less, the reification of an abstract emotion. The Red Lanterns represent rage; the one shown here is called Atrocitus, and first appeared in GREEN LANTERN #28 in 2008. [ETA: That issue also mentioned, for apparently the first time, "the massacre of Sector 666," which caused the Guardians to try to deactivate the Manhunters. And if we see Manhunters again in this series, I'll attempt to explain them, which will take a while. Otherwise, move along, nothin' to see here...]
The Orange Lanterns represent greed; this one is called Agent Orange. The Yellow Lanterns represent fear; this seems to be Mongul, who was created by Len Wein and Jim Starlin and first appeared in DC COMICS PRESENTS #27 in 1980. The Green Lanterns represent will; here we have Hal and John again. The Blue Lanterns represent hope; we're seeing Ganthet and Sayd, two renegade members of the Guardians of the Universe, who started the Green Lantern Corps. The Indigo Lanterns represent compassion; no data yet on who this is. The Violet Lanterns represent love; the characters in the violet panel are Zamarons, for which I have no recourse but to bump you over to their Wikipedia entry or we'll be here all night. The last panel would appear to be a black lantern power battery, which per GREEN LANTERN #25 contains the body of the Anti-Monitor. (What's an Anti-Monitor, you ask? We'll get to that one of these days.)
This is a flashback to a scene from CRISIS ON INFINITE EARTHS #10, in which the Anti-Monitor is fighting the Spectre. Specifically, this is the Jim Corrigan version of the Spectre (created by Jerry Siegel and Bernard Bailey; first appeared in MORE FUN COMICS #52 in 1940). Corrigan was replaced as the Spectre first by Hal Jordan and then by Crispus Allen.
This, in fact, is the Crispus Allen version of the Spectre (created by Greg Rucka and Shawn Martinbrough; first appeared in DETECTIVE COMICS #742 in 2000; became the Spectre in INFINITE CRISIS #4). Depictions of the Spectre over the last 40 years tend to seesaw between the kind of ultra-cosmic struggle we've seen on the previous two pages and the kind of punishment-fits-the-crime grossouts we're seeing on this page. Carr D'Angelo is named after the real-world person who owns the store Earth 2 Comics.
It's unclear who's falling here--could be the Flash, could be Darkseid, could be Orion. [ETA: Geoff Johns says it's Darkseid; I suspect it's not that simple, especially since Darkseid was killed on Earth in COUNTDOWN TO FINAL CRISIS #2.] But the image of falling through two-dimensional planes (like comic book panels) that have been rotated through three-dimensional space recalls similar images in Morrison's SEVEN SOLDIERS OF VICTORY project, especially the MISTER MIRACLE miniseries. The reddish and blackish planets in the first panel might be Apokolips and New Genesis, the warring planets in Kirby's "Fourth World" comics, although it looks like there's more of a nature/tech dichotomy than a good/evil dichotomy going on there.
Panel 1: "A runner poised on the line": another suggestion that our narrator is some version of the Flash.
Panel 2: Left to right, we're seeing:
*Dr. Light (I): created by Gardner Fox and Mike Sekowsky, first appeared in JUSTICE LEAGUE OF AMERICA #12 in 1962
*Killer Frost (II): this version created by Gerry Conway and Raphael Kayanan, first appeared in THE FURY OF FIRESTORM #21 in 1984 (an earlier version had appeared in FIRESTORM #3 in 1978)
*Captain Cold: created by John Broome and Carmine Infantino, first appeared in SHOWCASE #8 in 1957
*Heat Wave: created by John Broome and Carmine Infantino, first appeared in THE FLASH #140 in 1963
*Giganta: created by William Moulton Marston, first appeared in WONDER WOMAN #9 in 1944
*Killer Croc: created by Gerry Conway and Gene Colan, first appeared in DETECTIVE COMICS #523 in 1983
*Mirror Master (II): original version created by John Broome and Carmine Infantino, first appeared in THE FLASH #105 in 1959; this version created by Grant Morrison and Chas Truog, first appeared in ANIMAL MAN #8 in 1989
*Shadow Thief: created by Gardner Fox and Joe Kubert, first appeared in THE BRAVE AND THE BOLD #36 in 1961
*The Human Flame: created by Jack Miller and Joe Certa, first appeared in DETECTIVE COMICS #274 in 1959
*Weather Wizard: created by John Broome and Carmine Infantino, first appeared in THE FLASH #110 in 1959
*Zoom: created by Geoff Johns and Scott Kolins, first appeared in THE FLASH: SECRET FILES & ORIGINS #3 in 2001 (based on Professor Zoom, created by John Broome and Carmine Infantino, who first appeared in THE FLASH #139 in 1963)
On the table is the Crime Bible, the sacred book of a religion of crime that appears to have links to Darkseid; it first appeared in 52 in 2006.
"The heart of Flash territory": they're apparently somewhere in Central City, the fictional city in which Barry Allen was based. And what's the presence Zoom is feeling?
Panel 3: The speaker appears to be Libra, created by Len Wein and Dick Dillin, who first appeared in 1974's JUSTICE LEAGUE OF AMERICA #111, in which he stole half of the Justice League's powers; at the end of that story, he attempted to become "one with the galaxy" and dissipated into nonexistence. It's not clear from that issue (reprinted in DC UNIVERSE SPECIAL: JUSTICE LEAGUE OF AMERICA #1 recently) what color Libra's eyes are--there's only one panel in which his eyes are visible, and they're colorless--but here they're definitely blue. (This is a suggestion that this Libra is Barry Allen, whose eyes were blue.)
It's particularly odd that the Shadow Thief is part of Libra's group, since Libra double-crossed him (and knocked him out) in Wein's story! He also betrayed Mirror Master, but that was apparently the earlier version of the character.
As for what this location signifies: Geoff Johns hinted (in the Newsarama interview linked from pg. 8) that it's something specific. The skyline behind the club on pg. 24 is drawn more or less the way Carmine Infantino used to draw it in old FLASH comics--but in those days it wouldn't have been a strip club. My best guess is that it's the former location of the Central City Community Center that was a nexus between Earth-One and Earth-Two way back in THE FLASH #123 and #137. (Judging from pp. 21-23, it's been redecorated, and now has very peculiar hexagonal skylights. Curiously, the plot of THE FLASH #137 has to do with peculiar "sky-lights," i.e. lights in the sky.)
"A new god": the characters in the "Fourth World" stories are the "New Gods."
"Believe in him, that's all he asks!" Libra seems to be talking about Darkseid here, but "believe in him" explicitly echoes the "believe in her" refrain chanted by the followers of Lady Styx (seen in 52 and MYSTERY IN SPACE), a goddess whose legions kill planets' entire populations and transform them into zombies--a process rather like the Anti-Life Equation.
The hand clutching something and crackling with energy alludes to a recurring image in DCU cosmology: a shape like a gigantic human hand, holding a cluster of stars, at the beginning of time. It first appeared in GREEN LANTERN #40 in 1965 (currently in print in Crisis on Multiple Earths: The Team-Ups - Volume 1 (Crisis on Multiple Earths)), and is generally the closest thing DC has to a creation-story icon.
It's rare, these days, for the Secret Society of Super-Villains to be referred to by its full name, rather than simply as the "Secret Society."
"And this is me": Barry is again implied to be Libra here.
If you look above that Infantino-style skyline, lightning plus red sky plus enormously oversized moon equals Flash costume. The scene suggests that Barry Allen has returned--or that, in any case, some version of the Flash has returned.
Here's where things get metaphysical: rather than death as such, what supposedly happened to Barry Allen is that he transcended time and was absorbed into the "speed force," eventually traveling back in time to become the lightning bolt whose strike gave him his powers. (This page is a guide to his post-life activities; the same site has this useful chronology of Barry's final days.) So it's not clear how he'd have become one with the universe in the same way as Libra, or would have returned from the great beyond as Libra.
The other possibility would be Bart Allen, Barry's grandson, who wasn't the Flash very long before he was apparently killed by Captain Cold, Heat Wave and Weather Wizard. The storyline in JUSTICE LEAGUE OF AMERICA and JUSTICE SOCIETY OF AMERICA that's now been collected as Justice League of America Vol. 2: The Lightning Saga coincided with that storyline; at the climax of it, it appears that members of the "Legion of Three Worlds" Legion of Super-Heroes have managed to capture Bart's spirit immediately before his death.
I assume "Twisters" is where the Society's meeting; Morrison has mentioned that this is where FINAL CRISIS proper begins, an instant after this scene. (Is the club's name a hint at something involving the Red Tornado? Or Barry Allen's children, the Tornado Twins?)
"Let There Be Lightning": the obvious allusion is to God at the beginning of Genesis, but see also the link to the ace of spades, above (pg. 10): "let there be light" as an initiation into mysteries.