At the Warner Bros studios in Los Angeles, young fans are eager to visit the set of their favourite TV programmes such as The Big Bang Theory and Pretty Little Liars, even if they might binge-watch some of these online. TV viewing watched within seven days of live transmission has been remarkably resilient for the past decade — about three hours, 34 minutes a day in 2016 compared with three hours, 40 minutes in 2006, according to Thinkbox, the trade body for commercial TV in Britain.