The world of HBO's Watchmen is a rich alternate history spinning out of the events of the Watchmen graphic novel. Executive produced by Damon Lindelof, Watchmen is a sequel to the seminal 1986/1987 graphic novel written by Alan Moore and drawn by Dave Gibbons (though Moore is not involved with the project while Gibbons is an executive producer). Described as a "remix" by Lindelof, his HBO series skips forward in time to tell a new story set in the world of the graphic novel. The story is set in an alternate present-day and maintains many of the core themes while also opening up the Watchmen universe even further.

Moore and Gibbons' Watchmen posited an alternate history where costumed superheroes existed and it explored how society was changed by their presence, especially after the arrival of the first (and only) superhuman being, Doctor Manhattan. The main story was framed as a murder mystery after the costumed vigilante/government operative Edward Blake, AKA The Comedian, was murdered in New York City in 1985. The graphic novel jumped back and forth throughout history to look at the rise and fall of the first team of costumed heroes, the Minutemen, in the 1940s, all the way through the dawn of the age of Doctor Manhattan, and the exploits of the Minutemen's costumed successors, a short-lived superhero team dubbed The Crimebusters (unlike Zack Snyder's 2009 film, the name Watchmen is not used as a team moniker in the graphic novel.)

The investigation into Blake's murder by the superheroes Rorschach, Nite-Owl, and Silk Spectre uncovered a massive conspiracy masterminded by the world's smartest man, Adrian Veidt aka Ozymandias, to prevent World War III - by murdering millions via a staged extra-dimensional (squid) attack on New York City, uniting humanity against this new threat.

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Lindelof's Watchmen picks up the story of the graphic novel (not the movie) 30 years later and treats the events of Moore and Gibbons' story as canon. (The series is also unrelated to DC Comics' Watchmen sequel Doomsday Clock.) HBO's Watchmen moves its setting to 2019 Tulsa, Oklahoma, a place a thousand miles and three decades removed from when Ozymandias 'saved' the world, but still reeling from the aftermath of everything that came before (as well from as its own checkered local history). Here is everything you need to know to get into HBO's Watchmen.

The Watchmen Graphic Novel's Alternate History Explained

The major divergences of Watchmen history begin in 1938, when Hooded Justice, the first costumed vigilante, debuted. This was followed by the formation of The Minutemen, the first superhero team consisting of Hooded Justice, the first Nite-Owl (Hollis Mason), the first Silk Spectre (Sally Jupiter), The Comedian, Captain Metropolis, Dollar Bill, Mothman, and Silhouette. The Minutemen were a 1940s fad and the team disbanded after a few years following the sordid deaths of several members.

The world of Watchmen changed forever when physicist Jon Osterman was transformed into the godlike Doctor Manhattan in 1959. Quickly co-opted by the U.S. Government, Doctor Manhattan's existence gave the United States an overwhelming strategic advantage over the rest of the world. This was evidenced by President Richard Nixon asking Manhattan to intervene in the Vietnam War, which was then won by the U.S. in three months. Doctor Manhattan's presence altered U.S. politics as well; the 22nd Amendment was repealed allowing Nixon to continually be re-elected (he is serving his fifth term in 1985).

Manhattan also changed technology; electric cars proliferated as did the use of dirigibles in New York City. However, the second wave of costumed superheroes in the 1960s and 1970s was short-lived and the introduction of the Keene Act in 1977 banned costumed superheroes entirely, forcing the second Nite-Owl (Dan Dreiberg), the second Silk Spectre (Sally Jupiter's daughter Laurie Juspeczyk) and others into retirement. The vigilante named Rorschach remained active in defiance of the Keene Act.

In 1985, with the Cold War escalating into imminent nuclear armageddon, Adrian Veidt aka Ozymandias hatched a conspiracy to save the world: he kidnapped prominent scientists and artists to create a giant squid-like monster, which Veidt would then teleport into New York City to simulate an alien attack on the Earth and cause the world's nations to cease hostilities and unite. In addition, Veidt plotted to exploit Doctor Manhattan's alienation from humanity to remove him from the planet.

Veidt's plan was discovered by The Comedian, so Ozymandias murdered him. The Comedian's death is what drew Rorschach, and later, Nite-Owl and Silk Spectre, into the investigating Edward Blake's murder, which led to them discovering Veidt's master plan. The superheroes, along with Doctor Manhattan, confronted Ozymandias but failed to prevent him from executing his plan - which worked. Nite-Owl, Silk Spectre, and Manhattan agreed to keep the truth about Veidt's plan a secret and Manhattan executed Rorschach when he threatened to expose Veidt (although he sent his diary detailing his investigation to The New Frontiersman newspaper). Nite-Owl and Silk Spectre went into hiding while Doctor Manhattan left the Earth.

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The Altered History of HBO's Watchmen Universe

Watchmen HBO

The history of HBO's Watchmen actually begins before the graphic novel's and centers on a real-life event: the Tulsa massacre of 1921, when mobs of white residents attacked the African American businesses and people of Greenville, Oklahoma in one of the worst incidents of racial violence in American history. The attack destroyed the wealthiest black community in the United States, which was known then as "Black Wall Street." Watchmen depicts the Tulsa massacre through the eyes of Will Reeves, a young African-American boy who survived the incident.

The events that occurred in the 30-year gap between the graphic novel and HBO's Watchmen include Robert Redford being elected President after Richard Nixon. In 2019, Redford remains President but his liberal ideologies have proven to be less than popular in many areas of the country. Redford passed the Victims Of Racial Violence Legislation (also known as "Redfordations"), which is a lifetime tax exemption for victims and descendants of designated areas of racial injustice in America - this includes the Tulsa massacre of 1921. Another notable change to Watchmen's America is that the American flag has more than 50 stars, indicating that other countries and territories have joined the nation as States, including Vietnam. Further, in Watchmen's world, fossil fuels are eliminated, electric cars are everywhere, and cellphones and social media don't exist, which are more gigantic changes from our reality. However, humanity still lives in the shadow of Doctor Manhattan, who is currently on Mars.

The Masked Tulsa Police

In HBO's Watchmen, the Tulsa Police Officers wear masks and keep their identities a secret thanks to DoPA - the Defense of Police Act, legislation that allows the police to hide their faces behind masks. The cops' modus operandi is in response to the White Night, a tragic incident that happened three years before the show when dozens of cops were attacked and killed in their homes by members of the Seventh Kavalry. Afterward, many terrified police officers quit the Force but those who remained where united under Chief Judd Crawford (Don Johnson) and adopted masked identities. This includes Detective Angela Abar (Regina King), who operates under the codename Sister Night, Looking Glass (Tim Blake Nelson), and Red Scare (Andrew Howard). The Tulsa P.D. operates under strict rules and they restrict the use of firearms unless they deem officers to be in imminent physical danger. The Tulsa Police always wear their masks in public.

The Tulsa Police are a twist on the first Nite-Owl; Hollis Mason was an NYC police officer who adopted a costumed crime-fighting identity. In fact, Chief Crawford keeps a copy of Mason's autobiography Under The Hood on this desk. In Zack Snyder's Watchmen, Mason (Stephen McHattie) said that the rest of the Minutemen were also cops who decided to don masks and costumes to fight bad guys. HBO's Watchmen's Tulsa cops seem to be spiritual successors to both versions of Nite-Owl but they're state-sponsored and don masks for self-preservation against their main enemy, the Seventh Kavalry.

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The Seventh Kavalry

HBO Watchmen Rorschach Cult

The Seventh Kavalry is a white supremacist group that commits acts of terror in Tulsa by targeting and waging war with the police. They are inspired by Rorschach and wear variations of the vigilante's inkblot mask. Many of them are suspected to live in Nixonville, a trailer park outside Tulsa that has a giant statue of Richard Nixon (their hero) at its entrance. The origins, members, and ultimate goals of the Seventh Kavalry aren't fully revealed by the conclusion of Watchmen's pilot episode, nor has the reason for their attacking the police in the White Night been explained. However, the Seventh Kavalry are well-organized and extremely well-armed and they have no issues with mercilessly using firearms against the police.

The Squids

Watchmen Squid Doctor Manhattan

One of the strangest occurrences in Watchmen's universe is that occasionally, tiny squids rain down from the sky. Angela and her son are caught in a squid rainstorm in Watchmen's pilot episode, which is preceded by an alert sound. The squid rain seems to be a frequent enough event that it's treated as a mere annoyance. When it's over, Angela casually wipes the squid parts from her windshield and continues on her way. Adrian Veidt's genetically engineered giant squid monster is referenced in the scene when Looking Glass interrogates a suspected member of the Seventh Kavalry, who seem to suspect (rightfully so) that the whole squid attack was a farce; the squid rain appears to be a mysterious offshoot of Veidt's creation but how and why squid rain from the sky is another mystery for Watchmen to solve.

Jeremy Irons' Character (Is Probably Adrian Veidt)

Christine Amery Tom Misson and Jeremy Irons in Watchmen Season 1 HBO

In Watchmen's pilot, Adrian Veidt is finally declared "dead" - but the show immediately cuts to Jeremy Irons' mysterious character, who is likely the man once known as Ozymandias. Now living in what looks to be the UK, Irons' eccentric character is fabulously wealthy and resides in a castle. He also claims he's writing a play and he is visibly moved when his butler Mr. Phillips (Tom Mison) presents him with a gold stopwatch - which more or less indicates that Irons is actually Adrian Veidt.

Mr. Phillips and the maid, Ms. Crookshanks (Sara Vickers) also behave oddly and it's possible they may not be entirely human; Ozymandias created genetically-engineered creatures like the giant squid and his prized pet, the giant lynx Bubastis. It's conceivable that in the 30 years since Veidt has moved onto building genetically-engineered humans and his doting servants are two of those creations. But whatever Veidt is up to now and how it affects the main Watchmen story in Oklahoma certainly bears watching.

NEXT: Watchmen Review: Damon Lindelof's Series Is A Radical Remix Of A Celebrated Comic

Watchmen airs Sundays @ 9pm on HBO.