Imagine an island in which ambitious narcissists are eliminated through a series of votes until only two remain. I refer not to the embarrassing spectacle of the race to become Prime Minister of the United Kingdom but to the alternate reality of Love Island. The opening episode of the fifth series on ITV2 was viewed by nearly six million people, over a fifth of them watching on a computer, tablet or mobile, with a total online audience of 1.33 million, including over half a million on phones.