It is a launch more reminiscent of a Harry Potter book than a lengthy, difficult novel by a Japanese author, but bookshops in the US are planning to stay open until midnight to cope with the demand for the translation of Haruki Murakami's 1,000-page trilogy, 1Q84.

There is a video trailer on YouTube and Spotify song lists of music associated with the jazz-loving author. Others have put up their own sections of translation on the internet for fans unwilling to wait the two years it has taken since the book was first published in Japan, selling an extraordinary 1m copies in two months.

Literary blogs have pored over revelations about plot and character and themes that Murakami has visited before – from love to messianic cults to cats and music, to his use of surreal devices. Murakami's English-language publishers, Knopf in the US and Harvill Secker in the UK, are anticipating an equally extraordinary level of interest when 1Q84 is published next month. The story follows the characters of Aomame, a hired killer, and Tengo, a novelist, whose lives increasingly overlap in a world that seems ever more unreal.

In the US, interest has been such that Knopf has already ordered a second print run. In the UK, Bethan Jones, of Harvill Secker, said inquiries from booksellers were running at 10-15 a day. "He is huge in Japan. Here he started out as an alternative, cult author. But this book looks as though it will be immense. It is really unusual for a book in translation, but we have produced a massive print run."

Following the runaway success of the book in Japan – its title is a play on George Orwell's Nineteen Eighty-Four, with the English letter "Q" pronounced the same as the Japanese word for nine, kyu – his publishers took the unusual decision to ask two of his regular translators, Jay Rubin and Philip Gabriel, to work simultaneously on the three books to speed up the production of an English version.

That in turn, as his British publisher Liz Foley explains, led to some contradictions in translation, which required arbitration by Murakami himself. "There is something really special about him," said Foley, mentioning how Murakami mixes up the everyday with the fantastical. "There is a cult element who are ardent about everything he writes, and that club is rapidly spreading."

Rubin also remarked on Murakami's ability to convey the commonplace in an extraordinary way. "What I love," he said, "is how he can describe eating yoghurt at midnight or the best way to cook a hamburger or someone pouring ketchup into a sock drawer. He is very down to earth, but also has passages that are very comically detailed.

"And it is not because he is writing about Japan that people love him. I'm not sure his readers are interested in Japan. It is about the moment to moment sensation of being in his world. Inside his head."

Rubin said the scale of 1Q84 was all the more extraordinary because when The Wind-Up Bird Chronicle was first translated its publishers abridged it, uncertain that there was a market for a Japanese literary novel of that length. These days at least there appears to be no question that Murakami's English-language fans will read anything that the marathon-running author writes.

One unresolved question is whether he is even finished with 1Q84. When the first two volumes were published in Japan in 2009, readers had no idea that a third book was planned for publication.

Rubin said that Murakami had left room to continue with the story of Aomame and Tengo – even hinting that there may be more to come. Speaking to a Spanish newspaper earlier this year, Murakami said: "A fourth volume featuring an older Tengo may come out. Who knows?"

The first two books of 1Q84 are being published in a single volume on 18 October and the third on 25 October.