HBO's Watchmen has a couple of Easter eggs that shoutout to Zack Snyder's 2009 film adaptation. Executive produced and written by Damon Lindelof, Watchmen is set 30 years after the events of the classic graphic novel by Alan Moore and Dave Gibbons - not Snyder's movie. Lindelof's ambitious "remix" of the superhero saga tackles many of the same complex political themes but he transplants the main story from 1985 New York City to 2019 Tulsa, Oklahoma.

Snyder's R-rated Watchmen remains controversial; while its fans praise the director's adherence to the source material, coupled with Snyder and cinematographer Larry Fong's striking visual style, the film's detractors claim the film's slavish adaptation doesn't capture the intricacies of the graphic novel and they question Snyder's hyper-realistic violence and his choice to give the film a different ending. However, the legacy of Snyder's Watchmen continues to endure and spark debate; the film has earned its place in superhero cinema thanks to its superb casting, stunning costumes, and impressive production design. But when conceptualizing his version of Watchmen, Lindelof opted to stick to the original graphic novel with Gibbons' blessing but not Moore's - though the reclusive writer disavows any adaptations of his books. Lindelof's HBO series holds the comic books as canon and serves as a sequel to that story. However, the shadow Snyder's film casts is unavoidable and HBO's Watchmen found subtle ways to acknowledge it.

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While Lindelof's Watchmen is certainly violent in its own right, it's during a quiet moment during the pilot episode that a clever nod to Zack Snyder's movie can be heard. Tulsa Police Chief Judd Crawford (Don Johnson) and his wife Jane (Frances Fisher) have dinner at the home of Detective Angela Abar (Regina King), her husband Cal (Yahya Abdul-Mateen II), and their three adopted young children. Angela also goes by the costumed identity of Sister Night and it's evident she and Judd are close friends, as evidenced by how Judd charmingly broke into song at Angela's prompting. During the dinner scene, a song can be heard in the background and it's a version of Nat King Cole's "Unforgettable" - the same song that played in the opening scene of Zack Snyder's Watchmen.

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Zack Snyder's use of "Unforgettable" lived up to the song's title: In Watchmen 2009's explosive opener, a mysterious masked assailant (later revealed to be Adrian Veidt, played by Matthew Goode) attacked Edward Blake, AKA the Comedian (Jeffrey Dean Morgan), in his New York City high-rise apartment. The incredibly brutal fight scene ended with Veidt tossing Blake through a window so that the Comedian plummeted to his doom - but the whole time, the bloody fight to the death was set to the melodious vocals of Nat King Cole.

"Unforgettable" was also utilized in the Watchmen graphic novel; it's the backdrop song for the TV commercial hawking Nostalgia, a fragrance by Adrian Veidt's corporation. Nostalgia is a recurring theme in Watchmen - as Sally Jupiter (Carla Gugino) said, "the past, even the grimy parts, look brighter all the time" - but Snyder used the song ironically as Edward Blake finally got payback for all of his past sins, even though it turns out he was attacked by Veidt because he learned of Ozymandias' secret scheme and felt guilt and remorse over Veidt's planned mass murder.

There's also a second Snyder Easter egg in HBO's Watchmen: throughout the pilot, there are TV commercials for a documentary called American Hero Story: Minutemen, an expose about the original generation of costumed superheroes. Prominent in the ad is Hooded Justice, who looks very similar to how he was depicted in the Watchmen movie. This is a nod to one of Snyder's strengths: his keen eye for superhero costume design. In Watchmen 2009, Hooded Justice and the Minutemen had costumes made of cloth and materials that are appropriate for their 1940s era. The depiction of Hooded Justice in HBO's Watchmen very much leans into how Snyder's styled the character and it's an understated show of respect to the director and his film.

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