The most famous lines of the film, in which the space-travelling replicant Roy Batty (Rutger Hauer) talks of his experiences being “lost in time, like tears in rain”, are absent, presumably because the book had long been sent to the printers by the time Hauer adapted the script.
Despite their wobbly quality, novelisations were at one point a large plank of film marketing. The original Star Wars novelisation, ghostwritten by Foster but put out under George Lucas’s name, was released six months before the actual film arrived in May 1977. By then, the book had sold millions of copies. All its readers first encountered the sci-fi juggernaut with the words “another galaxy, another time”, not “a long time ago in a galaxy far, far away”.
Novelisations were particularly useful in generating hype away from the big cities, in places where the local cinema might be a few months behind the release calendar. And when a film stopped playing, you would be lucky to encounter it on TV, making the only reliable way to relive it the novelisation.
Beneath these structural factors, however, was something simpler: more. For children especially, the wonderment of seeing a new universe conjured on screen spurs an urge to spend even more time in it. “A lot of people have this moment when they’re young, where they pick up a film novelisation and it gives them something the movie didn’t,” says Andrew Overbye, a co-host of a podcast, Authorized Novelisations, which discusses the format. “It can be this ‘Aha!’ moment.”