Drawing on a career in broadcast drama that included periods in charge of both EastEnders and The Archers, the producer John Yorke wrote a fine book called Into the Woods, which analysed the recurring principles of storytelling from Greek drama to  soap opera.And between those two genres, as Yorke pointed out, the plots are often interchangeable: infidelity, incest, spouse-murder, exile and external threat were as fruitful for Euripides and Sophocles as for the script­writers of Coronation Street and EastEnders. Yorke even admitted to giving production teams synopses of the major Athenian tragedies and, if a screenplay lacked incident or emotion, to issuing orders to “Greek it up!”He acknowledged, though, that there was one classic narrative that had proved impossible