When legendary writer Alan Moore and master artist Dave Gibbons teamed up to create Watchmen, it is unlikely that either of them realized they would be transforming the world of comics forever. Since its release, The Watchmen has gotten a movie adaptation, an HBO miniseries, spinoff comics, and even a handful of references on The Simpsons.

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One of the most recent sequels was the comic Doomsday Clock by Geoff Johns, Gary Frank, and Brad Anderson. This sequel to the original comic combined the world of The Watchmen with the main DC Universe. Without naming anything too obvious, here are 10 hidden connections between Doomsday Clock has to the original Watchmen that you didn't notice:

10 Golden Age of Superheroes

The Golden Age is a term used to refer to the early period of superhero comics that emerged between the World Wars and ended in the mid-50s. Such characters as Superman, Wonder Woman, and Batman emerged during this time.

In the original Watchmen, Golden Age superheroes like the first Nite Owl and Nite Owl founded the concept of masked vigilantes fighting crime. Meanwhile, in Doomsday Clock, the DC Universe's Justice Society of America - the original superhero team - is written out of existence by Doctor Manhattan, even as the origin story of Superman is pushed forward in time from him being a hero of the 30s to a contemporary superhero.

9 The Nature of Time

Time is a major motif in The Watchmen. Doctor Manhattan's father is a clockmaker who abandons his profession after learning that time is relative. After the accident in the lab gives Manhattan his powers, he is able to perceive the shape of time as simultaneous events all happening at once without a sense of past or future.

Interestingly, the end of Doomsday Clock changes this. Time can be altered. Some things may seem preordained, but Doctor Manhattan shows that both the past and the future can be altered and that Superman's origins are tied to the flow of time in the DC metaverse.

8 Rorschach's Journal

No one is ever likely to forget Rorschach's Journal. The opening line of The Watchmen begins with a passage of the journal reading, "DOG CARCASS IN ALLEY THIS MORNING, TIRE TREAD ON BURST STOMACH. THIS CITY IS AFRAID OF ME. I HAVE SEEN ITS TRUE FACE." Later, Rorschach's Journal exposes the lie Adrien Veidt used to save the world, effectively triggering a nuclear war.

Johns recreates the tone of these journals in his sequel with prose that updates the visceral trauma and political rage for the age of smartphones. However, the poetic irony here is that the journals reveal truths that actually lead to the world being saved in Doomsday Clock.

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7 The Photograph

There is a photograph in Doomsday Clock which appears wherever Doctor Manhattan goes, copies of this same picture manifesting at different points in time throughout the DC Universe. The original picture was taken at an amusement park in 1959 when Doctor Manhattan - still just John Osterman - was on a date with his soon-to-be wife Janey Slater.

The photograph itself is an obvious artifact, but its symbolism is what's important here. A photograph is a moment frozen in time. Jon is obsessed with time, seeing all of it simultaneously. As he begins to accept that time is not static but malleable, he carries with him a memory of a lost timeline - and of a lost love - the photograph ensuring he will never forget either.

6 The Angry Mob

Time and again in the original Watchmen, there are shots of an angry mob. Whether during the crime wave of the 70s, the prison riot, or the panicked crowds in New York at the story's end, the mindless panicked mob seems to be a constant threat in the world of Moore's comic.

Not only is Doomsday Clock full of rioting mobs like the one in Moscow protesting US meddling in world affairs, but there are repeatedly scenes of mobs in Doomsday Clock that directly reference similar moments in Watchmen, like the prison riot or crowds gathered with their protest signs in the opening issue.

5 US-Russian Relations

As The Watchmen deals with Cold War politics, the rivalry between the United States and the Soviet Union makes sense, especially as the story deals with fear of the Bomb.

Since the end of the Cold War, the geopolitical landscape has changed dramatically. Doomsday Clock pays homage to the nuance of modern diplomacy in China and the Middle East. However, the main showdown is between the US (which is in an uproar over the Superman Theory) and Russia under the leadership of Vladimir Putin. This Russian-US tension is a direct homage to the original Cold War drama, updated to address contemporary imperialist trends.

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4 Rightwing Extremism

Alan Moore is an anarchist and has never hidden his politics. One of the central themes of Watchmen is a critique of rightwing political forces in superhero comics. The hero Rorschach is an Objectivist who uses unrestrained tough-on-crime violence to sadistically torture people, while the Comedian seems to embrace Kissinger-style political realism, committing war crimes for the sake of his county's national interests. The last page even mocks President Reagan (though coded by invoking Robert Redford).

Doomsday Clock is less overtly critical of rightwing policies, but has several not-so-subtle digs at Donald Trump. Also, the last issue has a red-hatted bigot commit a hate crime, clearly a nod to the huge number of white nationalists wearing MAGA hats.

3 Mental Health

This is not a huge theme in The Watchmen, but it is one central to Rorschach's character. Rorschach suffered childhood trauma, leading to his extreme behavior and delicate grasp on reality. Another mental health issue concerns one of the original Minutemen, who was hospitalized after a mental breakdown.

Johns returns to this theme, creating a new Rorschach who suffered psychological trauma following the squid attack in New York. He meets Mothman while in the psychiatric ward. It takes an extreme personality to dress up in a costume and fight crime. For someone without powers, it seems madness is just as likely as bravery to inspire such vigilantism.

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2 Childhood Trauma

An extension of the theme of mental health is the direct role childhood trauma has on shaping superheroes. The first Nite Owl writes in his memoir about someone he knew who committed suicide when he was a boy. Both Rorschach and the second Silk Spectre suffered childhood traumas as well.

In addition to the trauma that impacts the new Rorschach at a young age in Doomsday Clock, there is a close parallel between Batman and Rorschach, both of whom turned their childhood pain into action. Also, Doctor Manhattan's decision to kill Superman's parents is a source of childhood trauma that literally alters the DC Metaverse.

1 The Doomsday Clock

This last entry is not subtle, but it is a multilayered reference. Throughout the original comic by Moore and Gibbons, there are constant references to the Doomsday Clock used by The Bulletin of Atomic Scientists to predict how likely it is for Earth to end in thermonuclear armageddon.

Not only did Geoff Johns name his sequel comic after this device, but he also decided to put a new spin on the clock. At the end of the comic, Doctor Manhattan has destroyed all nuclear bombs on Earth. The clock is reset. Instead of a symbol of doom and the world's end, the Clock becomes a symbol of renewed hope for the future.

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