Follow an alternate reality that closely mirrors the contemporary world of the 1980s. The primary difference is the presence of superheroes.
The point of divergence occurs in the year 1938. Their existence in this version of America is shown to have dramatically affected and altered the outcomes of real-world events such as the Vietnam War and the presidency of Richard Nixon. In keeping with the realism of the series, although the costumed crimefighters of Watchmen are commonly called \"superheroes\", only one (Doctor Manhattan) possesses any superhuman powers.
The war in Vietnam ends with a U.S. victory in 1971 and Nixon is still president as of October 1985. The Soviet invasion of Afghanistan occurs approximately six years later than in real life. When the story begins, the existence of Doctor Manhattan has given the U.S. a strategic advantage over the Soviet Union, which has increased tensions between the two nations.
Eventually, superheroes grow unpopular among the police and the public, leading to the passage of legislation (the Keene Act) in 1977 to outlaw them. While many of the heroes retired, Doctor Manhattan and a veteran superhero known as The Comedian operate as government-sanctioned agents. Another, Rorschach, continues to operate outside the law.
A seminal piece of work, this is a rather deep and mature exploration of some unique concepts. Whatever you think of superheroes, this is probably not quite what you'd expect.