In some cases it might not be that deep, though. At least, not on an emotional level. Psychologist Dr Joan Harvey at Newcastle University agrees that the nostalgia factor allows you to "relive a little bit of your past," - and there's absolutely nothing wrong with that, of course - our adult fascination with teen films might just have something to do with the direction of popular culture at the moment. "We are more likely to admit to enjoying those things than we were a few years ago," she explains. "It has become more fashionable to like [teen entertainment] and to say you enjoy them. It’s perfectly fashionable, as an adult, to be re-reading Harry Potter. Ten years ago, you probably wouldn’t, although you would have watched the films … there are a lot of secret watchers."