Producers have always had a tendency to prefer known material – if something has sold once, it might sell again – but the combination of a recession and escalating digital competition for audiences have made theatres even keener for people to know what they are going to get. So it is unsurprising that two of the summer openings should be cultural products broadly familiar even to those who have not consciously consumed them. You do not need to have read Kafka’s The Trial to know that it is about a bloke who is woken up on his birthday to be told that he is being investigated for unspecified crimes; and, without being an acknowledged fan of Burt Bacharach, most people could hum his tunes for such Hal David lyrics as “I’ll never fall in love” and “R