WARNING: The following contains major spoilers for the seventh episode of Watchmen, "An Almost Religious Awe," which premiered Sunday on HBO.

Over the course of the past seven episodes, HBO’s Watchmen has subtlely built up a world with a fascinating alternate history that inverts and reflects the real world in a number of surprising ways.  The show has already highlighted a popular Ryan Murphy-esque drama series called American Hero Story, acknowledged the lengthy presidency of Robert Redford and shown that Steven Spielberg directed a film about Adrian Veidt’s destruction of Manhattan instead of Schindler's List.

In this week's new episode, "An Almost Religious Awe," flashbacks to Angela's childhood in Vietnam teased the connection between that world's real costumed crime-fighters and that world's fictional superheroes.

Early in the episode, Angel tries to rent a videotape of the movie Sister Night, which features an African-American vigilante who marks a clear inspiration for Angela's masked alter ego. Now, HBO has revealed a few more details about Sister Night and the genre that inspired it in this week's "Peteypedia" entry, an online repository of ancillary reading that replicates the original comic's backmatter. While describing the Sister Night film, the document reveals Batman's similar role in the Watchmen universe.

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Watchmen Sister Night videotape

Peteypedia is a collection of documents collected by series character Dale Petey, an FBI Agent attached to the Anti-Vigilance Task Force. In his assessment of Sister Night, he describes it as part of the fictional "Black Mask" genre. In response to the growing number of African-Americans who moved to Vietnam after America's victory in the Vietnam War, this genre rose up as a response or critique of masked vigilantes.

Alongside Sister Night,  one of these exploitation films was called Batman.  Petey goes on to identify Batman as a direct response to the tech-based, human hero archetype that Nite Owl established. While the comic book’s Nite Owl was more based on the Ted Kord version of Blue Beetle, they're both still part of the same tradition of human heroes who rely on their wits and gadgets to fight crime. Both characters are also based on nocturnal animals and have hi-tech tools like their own aircraft.

Daniel Dreiberg, Watchmen's Nite Owl was hardly the model of physical perfection that Batman is often considered as. He was overweight and often lacking in self-confidence. Still, making him the inspiration for the character who's one of the real world's most famous superheroes adds a hefty layer of irony to the show's proceedings.

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Watchmen Superman Action Comics 1

While this movie Batman remains unseen, he almost certainly isn't the Bruce Wayne we know from comics. Considering the context of the memo, he's quite possibly African-American, and there's no telling what else might be different about this cinematic Batman.

Although the series already established Superman as a foundational part of Watchmen's wider world, this obscure mention apparently gives Batman a very different place in it. Even though he's a bona fide multimedia superstar in the real world, Watchmen's Batman is apparently a far more minor figure, and it's not even clear if DC ever introduced Bruce Wayne after the first wave of costumed vigilantes emerged.

While this mention ultimately raises more questions than answers, this detail is just one more thing that enriches the rich history of this slightly askew parallel reality.

Developed by Damon Lindelof, HBO's Watchmen stars Jeremy Irons, Regina King, Don Johnson, Tim Blake Nelson, Jean Smart, Louis Gossett Jr., Yahya Abdul-Mateen II, Tom Mison, James Wolk, Adelaide Clemens, Andrew Howard, Frances Fisher, Jacob Ming-Trent, Sara Vickers, Dylan Schombing, Lily Rose Smith and Adelynn Spoon. The series airs Sundays at 9 p.m. ET/PT.

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