Supergods: Our World in the Age of the Superhero, By Grant Morrison

Is it a bird? Is it a plane? Is it human destiny?

Like a primary-coloured blur streaking across the skies, Grant Morrison's Supergods arrives just in time to put the summer invasion of the cineplexes by an army of garishly costumed superheroes into historical and social context.

The superhero is a part of modern life. Aside from those of the twin pantheons of American comic book publishing, Marvel and DC, superhero-style characters can be found infiltrating all aspects of the media, to sell cereals or insurance, fronting newspaper finance columns or car washes. But it wasn't always so. It wasn't until 1938, one of the dark years between the US Depression and the start of the Second World War, that Superman made his appearance in the debut issue of Action Comics.

Morrison chronicles the ensuing different phases of comics history with relish and a fanboy's attention to detail. So the escapist fantasies of the war years give way to the space-age optimism of the Sixties, then via the dark, brooding, violence of Eighties incarnations to the post-modern, post-9/11 repositioning of the superhero.

There is no shortage of non-fiction treatises on comics culture, but Morrison's account differs in several ways. For one, he's no mere student of the art form: he has written the adventures of some of the most iconic figures in the world of comics, including Batman and Superman. But nor is this just an insider's eye view. Morrison has always been more of an outsider; his tenure on even the most traditional superhero titles was characterised by knowing, self-referential weirdness and radical, zeitgeisty re-imaginings.

Like the best superheroes, Morrison's book has a secret identity. Peel away the mask of social history and you find beneath a strange multi-persona'd beast. It is part "boy that comics built" memoir, detailing Morrison's upbringing in Glasgow in the Sixties and Seventies, his parents' break-up, his retreat into the world of four-colour fantasies and emergence into the comics industry via punk and Eighties nihilism. (His diary entry for his 19th birthday, in 1979, reads: "Soon I'll be twenty! Thirty! Dead dead dead!").

But perhaps what lifts Supergods above anything else on the market is the beating heart of the book: a rather outrageous account of a drug trip Morrison took in Kathmandu which, he says, exposed him to pan-dimensional intelligences who planted the seed in his mind that fiction is just another type of reality as viable as our own.

It's a big ask of his readers but somehow, in the context of the suspension-of-disbelief world he asks us to inhabit for the duration of Supergods, it works, especially when taken with Morrison's conviction that mankind is inevitably going to embrace its superhuman destiny thanks to spiralling advances in medicine and technology.

Supergods is a rather astonishing piece of work that leaves you feeling pretty much as those first readers of Superman in 1938 must have felt: slightly more aware of our place in the universe and cautiously optimistic about the future.