Unfortunately, it’s an air that dissipates as the series goes on. The issue is that there is a huge number of sequences in Good Omens that doesn’t involve Aziraphale and Crowley, and while all of that peripheral material boasts lavish costumes, decent digital effects and lively performances, none of it is anywhere near as tense or as funny as the central duo’s mission. There is a dishevelled witchfinder (Michael McKean, with an amusingly mangled Scottish accent) who hires a drippy new assistant (Jack Whitehall), and lives next door to a kindly sex-worker (Miranda Richardson). There is a 17th-Century witch (Josie Lawrence) who can see the future, and there is the witch’s beautiful American descendent (Adria Arjona), who tries to figure out what her ancestor’s prophecies might mean. And then there are the Four Horsemen of the Apocalypse – or the Four Bikers of the Apocalypse, as they’ve become – as well as the mop-topped Antichrist and his friends, who romp around an Oxfordshire village in blissful ignorance of their earth-shattering importance.

If that weren’t enough, we drop in on Christ’s crucifixion, the French Revolution, Shakespeare’s Globe and World War Two. We visit the shiny white headquarters of Heaven and the shadowy bustling corridors of Hell. And we hear God’s own narration, as voiced by Frances McDormand. All of these scenes are entertaining, in a self-congratulatory sort of way. But how much do they have to do with whether an angel and a demon can prevent the destruction of mankind? For most of the series, the answer is very little.

The tangential structure won’t put off the book’s devotees, who adore it not for its plot but for its studenty jokes, its mischievous commentary on Christianity, and its leaps from continent to continent, and from century to century. But everybody else will be asking if it was strictly necessary for the series to ramble on like this for six hours.

To give you some idea of how leisurely it all is, the fate of humanity is resolved near the beginning of the last episode, which leaves about 40 minutes of loose-end tying: whenever you think you’ve watched the final scene, Gaiman adds another final scene and then another. That would be frustrating enough with any story, but it is particularly problematic when the story is about the ultimate race against time: the countdown to Armageddon. Let’s face it, if a TV series can’t imbue the imminent obliteration of everything and everyone on the planet with a sense of urgency, then it has to be doing something wrong. Animated signposts keep swinging onto the screen to tell us how many days and hours are left until doomsday, and yet Good Omens meanders along as if it had all the time in the world.

★★★☆☆

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