Actually, both the TV series and the graphic novel are set in an alternate universe which has been changed in all sorts of subtle ways by the presence of numerous masked vigilantes and by one phenomenally powerful superhuman. In this universe, America won the Vietnam war, and Richard Nixon was the President for decades before Robert Redford took his place in the White House. Pagers and CDs are still popular, but battery-powered cars and high-flying hovercraft are the norm.

One electrifying thing about the series is that it never makes a big deal about any of these small divergences. There are no captions or speeches explaining how and why its world is different from ours, nor are there any flashbacks to the events of 1985. Instead, the viewer has the unsettling and exhilarating feeling of being dropped straight into an America where everything looks familiar until it suddenly doesn’t, and where there are new twists to be discovered in every scene.

If you are already a fan of the graphic novel, you’ll appreciate the ways the series updates and develops the scenarios created by Moore and Gibbons. If you’ve never read it (and if not, why not?), then don’t worry. Watchmen still works as a stunningly ambitious Orwellian science-fiction mystery, and one of the year’s most compelling TV shows.

Watchmen begins on Sunday 20 October on HBO in the US, and Monday 21 October in the UK on Sky Atlantic

★★★★★

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